I have the Eibach set and they stiffened it just right. BUT, the total cost was nearly $800. The place that did the install showed me the alignment sheet after the springs were installed and the camber & toe were way off. They had to swap the camber bolts and that added $$$ to the install. Even now, with the new set-up, I get uneven tire wear. The inside of the tires are completely bald, while the outside looks like its got 5,000 miles left. I am now looking to correct this as well.