Was between the Rancho 9000XL shocks or these. My 2500HD Duramax already had the Rancho 9000XL shocks with 97,000 miles and I ended up replacing them with the Bilstein shocks and it rides much much better than it ever did with the Rancho's. They do not adjust stiffness but they are a much higher quality shock and will not be going back to Rancho or a twin tube shock. My truck ride height is the exact same as before and the clunking sound in my front end is gone as my shocks work again. My two rear Rancho shocks were easy to compress by hand with a very slow rebound and the fronts I could compress with 2 fingers and absolutely no rebound. Go with these and be happy. Now we will see how long they last but they appear to be very high quality.The pictures I have attached are my rear shock.Update 3.3.17I now have over 10k on the new shocks and they are purely amazing shocks. Don't waste money on cheap Rancho's or others and go to the monotube shocks. No sway, bottoming out and rough rides anymore.