FE,
Just like people are different, pools are different.. Some pools get a lot of debris and some not so much. Some pools have saltwater chlorine generators, some do not.
Some owners don't care if "stuff" is floating in their pools and others do...
There is no right or wrong answer here.. Whatever works best for you, works for us..
In my case, there is no way I could run 4 hours a day, because I have a SWCG and I'm way more OCD about stuff floating in my pool than I should be..
I run my IntelliFlo pump 24/7, most of the time at about 1200 RPM.. I do this because I like to generate a little chlorine all the time, and I like to skim all the time.. And it costs me less than $20 bucks a month..
Logic says that running the pump 24/7 cuts the lifespan in half.. I don't know if that is really true or not, but either way, I don't care..
I actually have 3 IntelliFlo pumps that run 24/7. I am running an un-scientific test to see how long they will last. Not really why I'm doing it, but my plan is to report any pump failure as they occur.. One of the pumps has been running for almost 10 years, one for over 7 and one for almost 7.. My pools do not close so this is 24/7/365 operation.. My pass/fail criteria is 10 years, but I hope to get a lot more use than that.. Ten years would make my pump costs about $150 a year,
at today's pricing, but I bought these pump for less than $1,000 bucks when originally purchased. For me, 24/7 operation is well worth the $150 bucks a year.. Anything longer is just gravy.
I would not spend too much time worrying about ROI and just do what makes you feel good about your pool..
Thanks,
Jim R.