I don't know about F/T but I have some experiences with P/K.

I used to p/k small rats before feeding them to my snakes after they were weaned off rat crawlers. I noticed there was a higher chance of them refusing a P/K rodent than, when I just dropped the small rat live and let them stalk it, when they were offered live.

It could have been a fluke, I don't know, ball pythons can be finicky. It's not particularly scientific, just something I observed. I have some snakes who will eat anything I give them, and some who only want live and will turn their nose up at P/K 50% of the time.