Any time you lift the front any amount you are going to put a strain on the CV joint. I think I am going to have this foreman for a good long time, and did not want to mess with the cv joints if possible so I omitted the front lift because I will never run anything bigger than a 27" tire and from what I know that will fit fine with no lift.
I did the rear for the ride comfort, with just me on it I don't notice the smothness as I do when I have a little weight or the wife on the back or more likly me on the back and the wife driving Also (someone correct me if I am wrong) but the back will put a strain in the u-joint, but if I have to mess with that I am ok with it, but I don't think it has that great of an effect on the u-joint. Any how if you have any questions about them go to Hebco web site and email them, I thought the costomer service was great. I think the guys name was Raymond