The only reason I'd feed live is if I had an animal that wouldn't take f/t. I mean, I just see no real benefit from it, and a lot of benefits from f/t food if your animal will take it.
Only thing (well... only thing with a spine) I ever fed live was fish, but I stopped that once I moved to a place I can buy frozen silversides. It was cool watching my snakes go fishing, but that packet of fish in my freezer smells a heck of a lot less than the live ones did! Lasts longer too.