I have HD shocks on my 420SEL. They are the same ride as the comfort ones, just more heavy duty. Since your getting lowering springs, I would get the heavy duty ones, they will last longer. And despite what people say, they are the same stiffness. Ive had both.
93 300D 2.5 Turbo, Black/Palomino 273K
09 E350 Black/Black 41K