I just did the WallPeg stuff per the recos on this board. They're plastic but seem durable and very affordable. I just ordered straight off their website.
I will say at least on my Wall Control metal pegboard the Wallpeg clips in much more easily. The steel pegs have a metal retainer which is meant to be able to "wedge" snugly into "regular" pegboard, but there's really no "wedging" with steel (that'd be a press fit in metal terms). For the few metal pegs I'm using I had to chamfer the retainer on my belt sander to get it to start into the pegboard, and even then I sometimes have to tap it in with a hammer.
edit: you can mostly make out the WallPeg hooks here:
http://www.garagejournal.com/forum/showthread.php?t=352062