Maytronics Dolphin S300i vs. M500

Neal

Active member
Jul 11, 2012
28
SW Michigan
#1
Last spring I finally decided to invest in a quality robotic vacuum. Based on TFP reviews I zeroed in on Maytronics Dolphin. So, to begin this is a report rather than a problem, and I hope that it may be helpful to others. I knew that a quality robot would not be cheap, but I was more concerned about the results of the vacuum and the quality/durability rather than the specific price. Last winter I was doing my research and was very interested in the M500. Fortunately, I had a dealer 15 minutes from me and they had a demo unit, which they were very helpful with. Once the pool was open I got the demo unit and used it for 3 days. It worked great, with one exception. I have an in pool table on a pedestal with seating and the distance between the seats and the pedestal was approximately the same width as the robot. The robot would eventually find its way to that table pedestal, get stuck and never back away. It did this 100% of the time. I called the dealer and they felt that there was no solution and that no robotic vacuum could handle this specific situation. I was thinking of what I could do to temporarily block that area, but my wife was not keen on this solution for an $1800 robot! Finally, I called Maytronics customer service and their recommendation was to try a Dolphin S300i. I was a bit surprised since the M500 was supposedly their top of the line, but they told me the search function in the S300i was newer and may handle the problem differently. My M500 dealer did not carry the S300i (apparently Maytronics has exclusive relationships for the sale of many of their robots), but 5 minutes away was a different dealer that sold the S300i. They had a new demo unit that had not even been out of the box and told me to keep it as long as I wanted! I only had it 3 days and to my amazement Maytronics was correct. The S300i would go to my pedestal problem area and momentarily try to get behind the table, but within 10 seconds it would turn around a leave! Maytronics customer service was correct! This almost sealed the deal for me, but I still wanted to fairly compare the features, quality of cleaning, etc. Both the M500 and S300i did an outstanding and comparable job cleaning the pool. I really like the modular design making repairs, when that time comes, much easier and hopefully less expensive (if out of warranty). So, I did purchase the S300i and this was my reasoning in my head to head demo comparison. Yes, the units are somewhat different with one big difference being that the M500 has two motors vs. one motor in the S300i, although for me the cleaning ability seemed the same. The big difference was the ability of the S300i to handle my table pedestal issue. Unfortuntately, I could not leave the M500 in my pool unattended and expect that it would finish its cleaning cycle since it got stuck 100% of the time. I really liked the single S300i basket rather than the two smaller M500 baskets. The single basket is quicker to clean (which I do after every use) and should handle leaves better this fall (but, I could test this). The S300i is lighter, probably due to the single motor, which my wife really appreciates. Don't underestimate bending over to lift the robot out of the pool if you are standing on the decking! Both units look pretty similar and come with a cart and the cart is quite handy. The anti-tangle device on the cord of both units works very well. Finally, the phone app works fine, but honestly I don't use it that often. After about 3 months of using the S300i I could not be happier and I consider this one of the best purchases I have made for our pool. The pool is sparkling clean and it takes just minutes to toss it in the pool and to clean the filters when done. No, it isn't cheap, but I was tired of the manual cleaning. Both of these models are not to be sold on-line, but I know that it is possible to find them. Maytronics states that the warranty is void if you buy it on line, obviously to protect their dealers. I decided to buy from my local dealer since they were very nice in loaning a demo unit. They also repair locally, if needed, and provide a loaner during the repair. I paid $1300 for the S300i and the M500 was $1800, so that was another factor. Both had a $125 rebate at that time and Maytronics was very fast at sending me a check (less than 30 days). In summary, this is my experience and thought it may be helpful to others. I know that M500 owners are very happy with their robot and experience as well. Honestly, if I would not have had the table pedestal problem with the M500 demo unit and had not called Maytronics customer service, I likely would have simply bought the M500. Both units seems to be excellent at cleaning and of high quality! I hope that this does not result in a debate of which unit is better, since I think both are excellent. I find TFP excellent for recommendations and I hope that my experience will be helpful to others looking for a robotic vacuum.
 

Gorilla83

Silver Supporter
Jul 2, 2017
313
Thornton, PA
#2
Thanks for sharing! We still have a ways to go before our pool is finished but we're also looking at both of those units. Nice to hear some real world feedback.

Do you have raised drains? Any issues getting stuck on them if so?
 

bmoreswim

Gold Supporter
Platinum Supporter
LifeTime Supporter
TFP Guide
Jul 16, 2012
4,313
Central MD
#4
Great summary of your thought process. Regardless we will have thoughts on which is better.

But that’s a ringing endorsement for one model over the other for a very specific situation that I’m sure some folks will greatly appreciate.
 

hem1tp

New member
Jun 26, 2018
2
Godley, TX
#5
Thank you for this; I have 3 stools on a raised ledge that I'm hoping whichever robot I choose can navigate. Do you know the width of your robot? I'm searching but finding dimensions is proving harder than expected. I also have several seating ledges I want my bot to be able to navigate and clean; beach entry ledge I'm willing to give the bot a break and not expect it to do, but I have 3 large underwater seating ledges I do expect it to clean and I figure the S300i or M500 are the finalists. Thanks for any tips

Tim
 

hem1tp

New member
Jun 26, 2018
2
Godley, TX
#6
I ordered/ received M500 from Margaret/ Marine P,S&P. I wanted app control-ability. I'm impressed but also not "overwhelmed". I don't regret my purchase by any means but the app leaves a lot to be desired; I must be standing over my power supply to bt connect and there's no countdown timer (clean cycle time remaining). It tries, mostly unsuccessfully, to clean my various ledges, seats etc but who knows if they are getting done as I don't watch it constantly. I have been running it multiple times a day since I received it with no problems. I clean filters about every 2nd cycle, pretty much to see what its picking up vice needing to be cleaned. I did brush down the pool after it finished final clean yesterday and I did not notice much remaining silt so that's a plus. I will still vacuum probably weekly and hand-brush down 2-3x week, but I'm a little more anal about cleaning the pool and we get a lot of dust/ dirt here blowing through the plains/ construction around my house in North Texas.
Overall, I'd say it's a good tool but I would have liked to have been able to test out other options as well.
I also run it in my spa and it handles that well also.

Tim
 
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Costas > DownUnder

Bronze Supporter
Dec 17, 2017
584
Adelaide | Australia
#8
I must be standing over my power supply to bt connect
I have heard this from others as well, yet my M500 app seems to connect & work easily from 15 to 20 metres away.

Note that you should face the front of the power supply towards your phone as the rear is all shielded by a metal plate which will prevent the internal BT antenna from being able to see your phone's BT signal.
 

smite

Gold Supporter
Aug 27, 2018
45
Chapel Hill
#9
I have narrowed down my choice to one of these two. Can anyone recommend a dealer with the best price. It looks like the rebate just ended in July. Are there any end of season sales?

I officially just got my pool today when I took possession of my new home.
 

React

Gold Supporter
Jul 5, 2018
78
Flower Mound, TX
#10
I have narrowed down my choice to one of these two. Can anyone recommend a dealer with the best price. It looks like the rebate just ended in July. Are there any end of season sales?

I officially just got my pool today when I took possession of my new home.
Marina Pool and Spa - You'll have to give them a call.

No rebates going on right now unfortunately as the one ended at end of July. I just purchased mine from there and guaranteed you won't find a better price.
 

Phugger

New member
Sep 10, 2018
4
Martinez, CA
#11
I just bought an S300i yesterday for my pool.
We just bought a house with a 30k gallon IG pool. I read enough here to know I needed a good robot, and the Dolphin series were the most recommended. I called Maytronics and had a discussion with them about the M500 vs S300i. She basically said the M500 was an older body style and a bit heavier, but functionally the s300i was on par, and recommended I go that option. I'm very impressed with what I've seen so far, but don't have any background on others with which to compare.

- - - Updated - - -

the s300i has an extended warranty right now. Extra year tacked on. Can't recall if it's 2 or 3 yr total, even though I just bought it yesterday.. When I get back over to the house, I'll check the paperwork and reply.
 

orthopod

Gold Supporter
Jan 12, 2008
106
Braselton, Ga
#13
Thanks for the review.
Our pool is being built right now. We will have a beach entry in one
Side and 4 stools in the pool. I’ve been worri d the robot will get stuck.

I think the 300 May be better for
Me based on this review.

I think someone asked on the site, but how wide is the 300?


Thanks!
 

jimim

Bronze Supporter
Jun 20, 2016
1,806
NE/Pa
#14
Thanks for the review.
Our pool is being built right now. We will have a beach entry in one
Side and 4 stools in the pool. I’ve been worri d the robot will get stuck.

I think the 300 May be better for
Me based on this review.

I think someone asked on the site, but how wide is the 300?


Thanks!
i have a 300i. like 15 inches wide maybe. not huge.

for what it's worth. . . when i talked with the dolphin rep he said fro more complex shaped pools and those with stools the 500 is the better choice. he said for simplier shapes and less obstructions the 300i was the choice.

i have a free form if u look in my thread. handles my pool fine. but u have the stools so he would have told u the 500. thats just 1 opinion though.

the beach entry i don't know how it handles that. i assume a sensor so it knows it is coming out of the water and then backs up to not beach it'self. mine has beached itself out of the water on steps 3 times so far. i have also caught it up that high on the last step and have seen it back down. so i guess a mixed bag.

jim
 

drew1240

New member
Nov 29, 2018
4
Roseville/CA
#15
Hello Phugger:

Congrats on your purchase. Is there a way to program the S300i to clean the water line tiles only without standing next to the controller? Do you have a raised drain? If yes, can the S300i go over it without problem?

Thank you so much!