mine have been eating live, one is 7 yrs old and the other is 4 yrs old and they have never struck at me or shown any signs of aggression, i do give them the occasional prekilled of course, but they are really nice, it mostly depends on the snake, all are different, but as for getting them fat, just feed them about twice a week, some large but not to big for it for two months and then start cutting down, that how i did it, when i got them they were very unhealthy and now they are perfect and in great health