well if you grew to a 24"+ plec what kind of room would you want? This is a big plec (not that your sailfin isn't. Your going to need a few hundred gallons IMO.
mine is very aggressive, still has spots at 9": {12" with tails} he was only $55 when i got him and attacked any other pleco i put in with him so watch out for your sailfin.
some cichlids and plecos arent always a good mix. But unless given ample room and hides, chances are it'll eventually conflict with your sailfin at the very least.