Frozen/thawed is the best way to go and will rarely if ever cause issues. I have not heard of over heating causing a regurg either.... typically if it is overheated the snake will refuse it. On the other hand if the prey item was not completely thawed then that could cause a the snake to regurgitate. There are several other reasons to offer f/t..... a f/t rodent is not going to bite and kill your beloved snake and the freezing process will kill most if not all parasites that are on or in the rodent. A live rodent can carry anything and everything that it has come in contact with at the pet store. Hunting instincts is not a reason to offer live, in fact the only person that is enjoying the hunting instincts is you. To confirm that ask some of the ball python owners here what it is like to try and get a ball python to start eating again after it has been attacked by it's prey.