I bought they're lift blocks for my truck (haven't put them in yet), but they look to be of high quality and as mentioned, I had a great experience with their customer service as well.
They put the lift on my last truck. 2inch body lift with a 3inch suspension lift. Products were great and there shop was very helpful/ friendly. I actually live down the road from there shop. I don't know anything about four link or traction bars.