Originally Posted by donn
While the tailpipe emissions "might" be cleaner than a 99 Ford Diesel for instance
There is not "might"...today's diesels are many times cleaner than the '99's were. Seriously, it's not even close. Just drive behind one when they need to step on the go pedal. All that black smoke is soot, and emissions. You won't see that on an '08 or newer truck (unless the DPF is gone).
As for the OP, don't let the DEF scare you away from a new truck. Add it every oil change and go on your way. My father LOVES his '11 F250 with the 6.7 diesel, and it gets 2-3 MPG better than my '08 empty or loaded.