I've always used Bilstein shocks and have always been extremely satisfied although my Kelderman air suspension came with Rancho RS9000XL adjustable shock for the front and no shocks for the rear, I elected on installing Bilsteins..
It doesn't get below freezing around here (30's to 40's) but my Rig sure likes starting on a warm engine.. It's quiet and the cab is nice and warm when I get in... Just-Sayin.. CROZ..
I just picked up my Rig from Valley Truck Accessories (Dentonis) in Stockton, California. WHAT A DIFFERENCE...! I had the Front (2 bags) and Rear (4 bags) 4 link with Auto height w/ dual rear dump valves installed. The system allows for stock height but I think they gave me a couple of inches...