I thought you said "bumpy road", Spring Creek is rated 6-8.
Off topic, I dont know if you ever check out colorado4x4 but look who posted a trip report...
http://www.colorado4x4.org/vbb/showt...TURE-5-17-5-21
Edit: Found more info about the Sammi in case anyone is interested..
drivetrain:Mercedes 2.2 4cyl diesel, custom manifolds with Mitsubishi Mighty max turbo, top mount intercooler, Benz 4 spd auto (without overdrive 4:1 1st gear, 5:1 reverse), Sami 6.5:1 tcase, yota axles (Aussie locker in rear, 3.07 gears)
Suspension/steering:
yj springs front and rear, custom high steer ( to clear diesel oil pan), ifs yota PS box fed by Benz PS pump
tires: 36x13.5x15 iroks
etc: full removable rollcage, all joints drilled with a 3/8ths hole and cage is used to store air from the mercedes A/C compressor, 8k winch...