I was actually wondering the same thing. Do the 450's all have d80's, or were there other options? I'm buying a 450, and due to the gearing, she sure don't drive like my ex. I probably wont ever do any serious hauling, maybe some trailers here and there, so changing the gears wont be too big a deal to me.
Basically just buying the 450 because the deal is just too damn good to pass on it.