Wellll, normally I don't feed in a bag. I was having trouble with my aztec not feeding, and sometimes putting them in a small area that's dark will encourage them to feed if they're a bit, uh, shy, shall we say. She did eat. Unfortunately, she regurged two days later, so, right now she's on paper towel, and being fed in the viv. I may have to keep that regimen up for now. I do not feed on substrate. I know you love watching the thrill of the kill as your snake comes out of the substrate, but my amel eats just as voraciously on f/t mice. She strikes and constricts regardless of whether or not they are alive, and she does it in a feeder box on paper. I care about my snakes, so I don't want to create any more problems for myself than I have to. Things such as ingesting substrate is avoidable and easy. My personal choice.