Hi Ryan,
The Gibbiceps Plec (Glyptoperichthys gibbiceps) has a common name, leopard sailfin plec, which must be what your LFS are selling them by. They are very common over here and I have yet to see a LFS employee warn anyone how big these cute little fish get, over 18" and probaly nearer 24".
They grow very fast, mine doubled in size in about 3 months, and have a huge appetite for algae and veggies. They also excrete huge amounts, I dont have any pics but expect LONG strings of poo EVERYWHERE when he gets bigger. You need a big filter as well as a big tank.
They can be a nuisance in a planted tank and seem to be the fishy equivalent to a bull, charging through plants and kicking up quite a lot of dirt in their wake.
Despite this, they are very impressive when they get larger, mine is still a baby at 7" but amazes people who dont see him hiding before he charges out to grab a pellet.
Mine never ate any apisto eggs but he will eat bloodworm and is the only fish Ive kept that couldnt get enough brown hair algae, which makes him worth his weight in gold on its own!
At the moment my guy is in the process of being taken in by a fish shop when they have room for him in their display tank, it will be a very sad goodbye cos he is a real character and reminds the angels sometimes that they arent the kings of the tank at all!
Ken