I love my Promaster. I have had 1 Ford E350 based... and 2 Chevy based rigs. As a member of the Scrawny Little Old Lady club and just 5'4", it is the most comfortable van I've ever driven. Finally, I didn't have to add to the height of the floor in front of the driver's seat. (those that don't like it much tend to be over 6'1")
It is also the best handling rig of my four. The Ford was horrid at best. The two Chevys were good... the one with duallies the better of the two, of course. But with the addition of Sumos front and rear (beefed up bump stops) in my Promaster, there is little or no effect of normal wind or passing trucks... or corners and driveways. The front wheel drive makes it easy to maneuver with its short turning radius.
The wider body also make it very roomy on the inside. Much better than the narrow Sprinters.
I personally wanted to avoid the expensive Sprinter (both up front and service costs) as getting 100-200,000 miles is irrelevant to me. And for the price difference I can pay for many years worth of gasoline. :C
But there is no getting around that the new Sprinter van has more bells and whistles, and is certainly prettier than my snub-nosed Promaster.