I feed mine jumbo mice also. There was just a very interesting thread on here about people possibly overfeeding they're snakes. I get mine from big cheese rodent factory. On average they're about 40 plus grams. I've seen what I believe to be healthy growth. My snakes look muscular, not over inflated. I weigh them regularly, and am consistently seeing their weights increase. I rarely offer more then one at a time. I feed them every 7 to 9 days. The thread was tittled, "let's discuss dietary requirements for ball pythons". I highly recommend everyone reading it. But then again, to each his own.