Yep - I tried them on both my 50# 5YO DS and my 30# 2YO DD1. Fit her great, but a hair too snug for him. Still, he said they felt nicer than his underJams. The GroVia fit him better (w/ plus-size tabs) without red-marks, but the rise is a hair too short (plumber-butt!) I stuffed one with two Flip Trainer inserts and they'll hold a single normal wet on him, but not two or a super-soak. Still, better than laundering sheets every day or endless boxes of sposies, and again: he says they feel better than the sposies. I hope they either make an older bedwetter pant or he stops wetting over the summer.
snap-ez makes both her trainers and diapers in youth and adult sizes. The youth-med is actually a bit too large on my 47lb 6year old on the tighter snap setting (probably should have ordered the youth-small) and you can stuff them with whatever you want. I'm still trying to find the perfect stuffers. Most nights he is fine, he can make it through dry or only wet a little so the infant bamboo prefold and microfiber towel hold fine but if he has a seriously heavy wetting night he still soaks through and wets the bed. He is my super heavy wetting child. I'm not sure if there is an insert out there I should be buying or if premium sized bamboo prefolds would be enough. They are really hard to find though. I think bamboo fleece would be ideal but I can't find it.