I only feed live asf males to my 880g male BP.... always supervised. I have NEVER had a problem with biting or scratching during feeding. He has bed fed asf for the past year and has a very strong feeding response. I would feel more worried feeding live rats than asf.
I, on the other hand, am bit by them on a weekly basis when cleaning their bin or giving food pellets. One I have actually named "Big Meanie". He has amazing accuracy at biting me right on my knuckles and not letting go. Guess what buddy? You're going next!!