I installed them on the back of my (wife) Grand Marquis '04 Ultimate Edition (with air springs/auto leveling system) and they are fantastic. The ride is better over bumps, and the rear end doesn't feel like it's skidding when it comes to bumpy corners on poorly maintained city streets. The ride isn't harsh at all - it feels comparable to the factory. But now there's definitely more control and better handling, and the sharp bumps in the road just disappear. The giant car is by no means a sports car, but combined with the 18-inch wheels and Michelin tires I drive now, it really is day and night. I didn't plan on replacing the A-pillars, but I'm totally doing it now. I originally only bought cheap Monroe "Sens-a-Trac" shocks, but one of them burned out on day one and they really didn't work properly. As usual, you get what you pay for. .One more note - take the SM5267 kit.Not everything is needed in this kit, but the presence of new nuts and the upper sleeve is convenient.