I had an Auburn in my last truck, best mod I ever had on that thing. Not sure who makes the best but all three are huge competitors and built very well. When I bought the Auburn I was looking at the Eaton. The place I got it carried both and said for the money he recomended the auburn. The auburn was actually a lil cheaper and this guy is a respected drag racer around here so I listened. They all seem to be great lockers, so I would just see what you could get the better deal on.
-Chris