I am going to disagree with you. Snakes have not been eating cornered rats and mice often. Unless you have massive enclosures where a rat can escape the snake the rat or mouse is cornered. Fight/flight... fight.
Cornered animals will defend them selves. A hesitant snake in the wild the rat will leave. There have been many captive snakes killed by rodents offered as food. Google it, rat kills snake, it is disturbing so I'll not post any photos. Live feeding MUST be supervised! There are risks associated with live feedings, more than with F/T.
There is a higher chance of internal parasites as well most wild caught snakes have them mites too for that matter. Most (not all) parasites will be killed with temperatures below -7ºC for 30-48 hours. The chances are higher of passing along parasites.
I am not saying one is better than the other but pretending that there are no risks is unfair to the OP. Understand the risks and make an informed decision.