my veiled used to love them (before he went on strike) the bigger the better! i found them very easy to keep, i have a few addult beetles at the moment, dont seemto be breeding...yet, i would try feeding the adults to you cham tho, there very hard, and smell foul! beetles taste bitter to chams aswell apparently, never eaten one myself tho, ....im blabbering agin...sorry, anyway,back to the point.... use the grubs as a treat more then a staple...
p.s never known one to bite...but theres a first time for everything...lol