I find the issue that people have with trying to get a live feeder to eat FT is either the prey isn't warmed up enough or properly, OR they don't do the zombie rat dance properly.

Ball pythons seem to be picky about how much movement they want in the prey. If you wave it around too much, the snake might get intimidated. Not enough and it doesn't catch the snake's interest. Once you master the steps of a good zombie rat dance, then you shouldn't have too much issue getting it to eat. I also seem to have to tug the dead rat's tail a few times once the snake hits it. I think the python believes it's "struggling" and so it really won't realize the rat was dead already. That's probably just me and my personal "old wives tale" type idea though.

Mostly I feed live because it's handier to me than having to dance a dead rat over and over on feeding day. But I'll be the first to say that a FT rat never bit a snake either. To each their own and there's no "one right way".