Yes people are running them. Some say they are 2 stiff. My Skyjackers were to stiff for a while. It was after a good trip to Moab and a run through the Rubicon that they finally started flex well. I bet you will find most springs stiff at first. Some may take longer to break in than others.
i am running a skyjacker 4" sua lift and it seems to perform fairly well. i purchased the springs fairly well worn so i didn't have to worry about breaking them in. you might consider doing this if you decide to go rancho. from what i understand aussie and rancho are the stiffest then skyjacker and hell for stout is supposedly the best......just my 2 cents. good luck