I always tell people to get plecos because they like them, not as a cleaner fish. Having said that, I feed all my plecos once every other day ad they still eat tank wall and rock algae. You should also consider the other fish in the tank, some male plecos can be very aggressive.
Different plecos definitely need different food. Most of the hypancistrus (Usually the "neat ones" are hypans.) only really thrive in a specialised setup. I kept Hypancistrus Contradens and Mega Clown plecos for a number of years and most of them were not aggressive feeders in a community setup and would be pushed out by other fish at feeding time.