I liked the look, and interior of the 07.5/08 Duramax. Granite, you have to do a DPF delete, and tuner, but it's well worth it IMO. Funnest truck I've ever driven. I drove a few 6.4 Fords, and the interior is nice, they just don't have the get up and go of the Duramax. I loved the Cummins motor, but just wasn't real fond of the truck around it. I've just heard too many people say there truck doesn't last half as long as there motor does in it. Any of the 3 will pull just fine IMO, but I think the Chevy is just the best ride for comfort, and after a few minor mods, this thing will haul the mail.