I know the animal stores say you should use frozen mice
There is no "You should feed F/T" what you should feed is what work for your BP and what is convenient for you.
dominate a live mouse at least a couple times through out his life
should not be the reason behind switching if you switch it should be because it is more convenient for you to feed live and not for the thrill.

Keep in mind if you switch your BP back to live you might have a hard time switching back to F/T so make sure it is really what you want to do.

Why do the people at the pet store recommend frozen mice then???
Could be one of those people that oppose to live feeding.