i don't have a perfect pull-up, but these look great for general use on regular pull-up bars.
They didn't look too good of quality though, and it doesn't look like it works on other pull-up bars beside the Iron Gym.
Does any one have any experience with ab straps though in general? Like, what's the difference between this and just hanging prone while doing ab exercises (my pull-up bar is high enough if I bend my knees and hang). It's not the price or anything: I just don't want unnecessary clutter/junk.