Well first of all, I have ASFs, because they are a permanent BP size that they wouldn't need any larger.

Rats are good because they have nice growth rates, and are useful for BP breeders at a very young age.

THEY ALSO DON'T SMELL AS MUCH.

My ASFs are clean, but my mice.. are not.. and rats are a bit better than mice.

Better pets and more intelligent too, from what I can tell. There is no proven nutritional difference, however.