My boy has only had F/T since his 4th feeding out of the shell. I'd like to keep him on that. I'm lucky in that there is a locally owned pet store in my town that has quite a large herp business. They have a variety of F/T in both mice and rats. Their stuff is a little more expensive than the big box stores but I'd rather pay a little more to keep it local. Besides, their customer service is amazingly good.