I have never had a snake injured from a live item. I can't use live rats though so I guess I can't say "I know what you mean". Here in Alberta it is illegal to have live rats so it makes it impossible for me to feed rats live to my snakes. But I do feed live ASFs... and I have been bitten by these guys. Its no walk in the park. But I have never had any issues with my snakes getting bit. Snakes are pros at taking down prey so it really isn't something you need to worry about.

As for fresh killed, I could never kill ASFs or mice myself so I again, I could not tell you how it works but it never hurts to give it a try if you are up to it.