powerlifting is just that. it focuses not on size but strength, mainly in the big 3, squat, bench, deadlift. in competitions the competitors are separated by weight class (114,123,132,148,165,181,198,220,242,275,SHW, i think there is another weight class between 275 and SHW but we didnt have it in texas high school PL)
you can check some PL routines at fortifiediron.com and get more info about it at elitefts.com. there are other sites but im fairly new to PL style training. i competed in HS but just did what the coaches told us to do. i never did much research on it until a few months ago.
benifits would be mainly in the numbers (and bragging rights). powerlifters put up huge numbers compared to body builders.
most powerlifting routines have a heavy upper/lower day and a
dynamic effort upper/lower day. the heavy obviously lets you stack the weight on and go for power and the dynamic effort day gives you the
explosive power to move heavy weights faster to apply more force to make you that much stronger. powerlifters also use bands and chains when lifting. do a search for "bands" or "chains" in some of the other forums and im sure youll find something on them.