We feed our rescue f/t... He takes it straight away and a bit of a tug after the first wrap which gets him to give it a better "hug". As others have said, live or f/t sometimes it is a matter of convenience for the human, or preference of the snake. Mikey has had no issues on coming out of his hide, and snatching a f/t adult mouse out of the tongs within 20 seconds of offering. Even if a missed strike or two, still a go getter...

We feed in cage with paper towels down over the substrate. When we doe this he seems to know it's time to eat. Please it keeps the substrate off the prey item.