It's just easier to sell them as a pair because of the bolt pattern. I don't want to deal with trying to convert the front to 5 on 4.5. I have wheeled the 30 pretty hard with the locker and 37's, and I haven't broke it. I'm just going to stick with the 30. Plus, I just bought that new bike, so there just isn't the money to build the front. I think selling them as a set is the better choice for me right now.