When I had my first ball python, I was also nervous about the move from mice to rats. However, it's been my experience that mice are FAR meaner than rats are.
I've fed live for the past 8 years, mostly rats. I've fed about 20K live feedings in that time. NEVER have I stunned an animal - I personally find that to be horrible advice - it only makes the critter that much more defensive and scared - especially if the come out of it while with a snake that decides they don't want to eat that week.
I also don't stand over my snakes with tongs in hand to intervene. Not even with my most expensive snakes. They are efficient at dispatching their prey without my intervention. I've had no significant injuries in all those feedings besides an occasional scratch - never anything that caused bleeding. Am I "lucky" after that many feedings? Nope - in my own personal data sample, let's pretend I had 3 significant injuries - that would be a 3 in 20,000 chance, or a 0.0001% chance of an injury. I have better odds of getting in to a car accident.
Other than for the occasional mouser, I feed rats exclusively and prefer them now - I did raise my founding females up to adult size on mice, because that's what I could get easily at the time. In my experience, they are not aware that they are about to become dinner and are found in the corner grooming themselves if a particular snake decides to take the week off from eating.