Love my Skyjacker
I have a Skyjacker 4. 5" kit and just put my first 4,500 miles on it over the past month. My kit is stage II (dual front shocks) but does not have the heim joints. My installer said to save my money unless I wanted to rock crawl, and that the base kit would give me enough articulation for the general off-road and mud I would likely see.
I haven't had it off road yet, but the lift seems to clear my 36" Swampers, and it drives beautifully on road. (although the Swampers make it sound like there's a B-17 bomber flying about 50 feet overhead... ) No pull on flat roads, and a slight pull to right or left if there's a crown. The mechanics who did my vehicle inspection and my first oil change both pulled me over to comment that the lift looked well engineered, safe, and properly installed. That said, I have a 4" Superlift kit on my 1972 CJ-5. I'm pleased with it and suspect that Superlift's kit will be good for our trucks as well. If you have questions about their engineering or what the kit includes, I'd start by calling or emailing Superlift.
Good luck!