I started breeding rats shortly after aquiring my group of Hondurans... putting me up to 12 snakes at the time. I only started breeding rats because rats were of feeding size at a much younger age than mice, so I could produce more food faster. I had 1.3 rats for a while, but I just scored some nice lab rat breeder cages so I will probably be upping my production a bit. I use the vanilla-in-the-water trick, change bedding once a week and the smell doesn't bother anyone in the house at all. Plus rats are kind of fun to watch and interact with so I enjoy the rat breeding greatly. And yes, it has saved me a LOT on feeder bills!