It seems that most people who have installed them were way back when the 4WP UCA's were the only ones available on the aftermarket. 4WP got the jump on all the other companies because they were chosen by Ford as an aftermarket partner, so they had CAD drawings and prototype Broncos way before anyone else to do their R&D. But since then the rest of the aftermarket suspension companies have come online with their own Bronco products so there's a lot more to choose from now. I think the ones from ICON, Camburg and the like are a better option. Disclaimer: I work for ICON and of course run their products on my own Bronco.