Well, just finished my first summer using a pentair ccrp150 cartridge filter on my 16 yr old 18' above ground pool(buried 2 ft in ground) and it was a success. Been using sand filters since day one and decided to go the cartridge filter route. Water quality outstanding and psi on went up only .5 in 5 months of use. Will be winterizing next week so it will be getting it's first cleaning.
When I was considering a cart. filter others on this forum advised I get the biggest I could afford as it would need to be cleaned less frequently. Glad I took their advise.