Put a set of Rancho 5000 on one XJ, kind of a harsh ride. Have a set of Koni´s on my other XJ now, solid but not harsh. Keeps the wheels on the pavement pretty good, without the sway and such from a softer shock. Seem to be a pretty good compromise, between comfort and stability. Though they do fade some with harsh use (get notably softer, when they are hot).