If you have 20 or more ball where do you get your rats?

[simplechamp]

I have 13 ball pythons and 3 boas. I purchase the rodents from The Mouse Factory; they are not the least expensive, but they offer the best product, in my opinion, and after having tried other less expensive alternatives.

So you have 16 snakes. Is it still more economical for you to buy as opposed to breed? Or do you buy for convienience, even though breeding could possibly cost less?