i own a 2004 sprinter, converted. 170 wheel base, solar, fridge, sink, queen bed, storage for days, insulated, AC and heat. its seriously amazing.
it is all dependent on your needs. do you want to do 4x4 off roading? stealth? big plus's to vans is you don't have to adhere to trailer speed limits. and generally better mileage. the sprinters get better gas mileage. mine is 23 hwy. where most dodges are lower in the mid to high teens.
after a bout a year or research, the best bang for your buck over a 10 year time period would be the ford transit conversion. larger, ok milage, but low service interval cost. they were a bit out of my price range when i found a killer deal on the sprinter.