Try AFR they are really easy to breed you dont have to clean the cage as often and the smell is really not that bad if you keep the cage clean you get almost no smell and they breed like crazy ! I have 4 trios and have way to many rats to feed all my snakes and im up to 12 snakes Hope this helps .
I think you meant ASF's (African soft furred rats) And they are very aggresive from what I have seen ackhem heard And to the OP make sure they are legal to own where you live they are illegal to own in california but then again everything is illegal here lol.