I have been lurking for awhile and finally made a purchase. I wanted to provide info on this forum to help others as they go through their journey of trying to find a robotic cleaner.
From all the research I did, I knew I wanted a Dolphin, but as you have seen and read, there are a mind numbing variety of options to choose from based on whether or not the models are offered in store or online. I was heavily leaning towards the Triton Plus (which is the same as the Oasis Z5 with a shorter warranty) and then stumbled on the newer S models. The S models are the same as the Active models, so Active 30 is the same as S300. Active 30i is the same as S300i and so on.
I found a local store who carries the S300. He raved about it and complained about the Dolphin marketing strategy as well (all the different names...very confusing). I walked out of the store with a S300 discounted to $1079 plus local taxes. Not the best deal, but better than the Oasis Z5 online and I have a local store who can work on warranty repairs instead of having to send it back to Maytronics.
I have only run it through one cycle so my review is limited, but it's simple to use. Plug it in, put it in the pool and turn it on. I will say that it didn't get every single thing in the pool, but with all the curves and steps, I don't know if there is anything out there that will automatically get everything. The one area it missed, I took over the robot with my phone and guiding it to that space and cleaned it up. Pretty slick. I really like the basket concept for the filter. It provides more capacity to put up larger items and is easy to remove and clean. That's a different set up than the Triton (Oasis) models, I think.
In summary, this is the S300, not the S300i. I controlled it from my phone so it does have the blue tooth capability. 2 year warranty. It doesn't use the ballast system like the Triton models to float to help climb the walls and clean the tile line. Watch their videos...it's pretty cool how it works. So the actual summary is that it's really cool
Hope this helps as others are looking. I'll periodically update here if there is anything I think will help others.