I'm running Camburg UCAs (ball joint) on my 4R. I kind of wish I had gone with the uniball joints but they are a couple hundred more dollars and I was on a budget at the time. I've read that the uniball joints have a longer life span but I have yet to see any tangible evidence to prove it. But if my UBJs fail, I believe I can replace them without replacing the entire arm. I've got Tuff Country uniballs on my truck and they do their job and have been for over a year now.