I like the superior ones the best, the advantages are rolled splines which are stronger than cut splines, and more importantly, they are the only kit that actually uses the stock AMC 20 axle seals. This means that if you you can go in any Jeep parts place and order an axle seal and it will work. Most other brands use special seals that you have to buy from the manufacturer so if you go this route buy extras to begin with, because when I worked in a shop, I had to turn away a lot of unhappy people cause we didnt have the seal that would work and they were stuck.