Well I feed live. Ive had a few little bites on some of my bigger girls. Nothing to bad so far. If done right live is safe. My balls all ive ever fed was live. The corns would take anything. I only leave my mice/rats in the tub for 5 or 10 min. I also dont leave the room either. I only have about 20 balls. Someone with a bigger collection it would be harder for them to watch every snake. Live has worked great for me I dont see myself switching over to F/T anytime soon.
I feed Mojo live and have since I have owned him(about 8 months now) and have never ahad a problem. I recently moved him from mice to rats and he is taking them like a champ. I am still newish to the forums so by all means any vets wanna add or correct me but I would say it is up to the individual snake and how agreesive of a feeder they are to deem wether proper size would be or nto be dangerous. Also from what I have researched if your going to mvoe it to rats be careful as rats are more aggresive then mice and in such can attack your snake before it attacks the rat.