Anyone have comments on Midway Specialties Sprinter sleepers,Phoenix sleeper packages,or Bentz Sprinter sleeper packages.What are the options that you would reccomend{must have}.Can you put in a double bunk? Positives and negatives are all apperciated.Are there other Sprinter upfitters out there? Is a backup camera setup a good idea? How do you keep warm and cool without a generator,without idling,or is a roof vent van a good idea? Thanks for the imput!