I picked up the 2016; but the air suspension model was $7000 more so I ended up going with standard 2016 suspension package (Mercedes High Center of Gravity). I believe it is better than my 2013 chassis was from the factory; but rear seat bounce is still an issue; as is buffeting behind large rigs (side roll when exiting driveway is not as bad in '15 chassis as 13; but may be because i now live in different house and driveway isn't as bad).
I would not upgrade to 2016 model for ONLY the suspension unless springing for the Air Package. I bet it is worth the $7,000 difference I would have had to pay - I'm sure it transfers to trade in/resale like 4x4 does on a truck. Just hard to swallow that I have a $150,000 van in the driveway and no Corvettes, SL600s or maybe even a Ford GT
We drove it to IL and back (1500mi) and I am VERY happy with the lane departure, screen doors, and electric window shades. The larger TV is nice (although the angle from 2nd row seats is still tough on the neck!
I also like the layout of the Electrical switches, generator and water heater controls being in the cabinet behind the driver, it's easier to access than walking all the way to the back when I connect to a 20AMP shore connection.
Still no clue why a Propane Cutoff wasn't installed in the Cabin (ahead of the exterior one); seems like that is a simple low cost improvement that does wonders to extend battery life! It was best mod I made to my 2014 model.
The addition of the cabinet over the curbside 2nd row seat is nice. (though loss of the storage below the 2nd Row Curbside seat is a bummer (we kept dog bowls, water and food & leash there).
RE: Lane Departure: the beep when you leave your lane gets really annoying when trying to read email messages (which was good since it forced me to have my wife read them to me and respond)
Not really advertised bonus was the LED light strip added to the awning & under the curbside frame, with controls on curbside front row seat with awning; making the van look pretty cool when parked with awning out.
The rear storage area now has LED lights on the left and right side; which seemed like a pretty cool idea, except once you pile in the bags the LED lights are not reachable! Placing them on the overhead would have seemed to made more since - so I'll probably still be installing a cabin light overhead in the far rear section.
There are also Clothes hanger hooks overhead on both port and starboard side behind the rear couch, as well as interior LED lighting in both the Front over cab cabinet, and rear center cabinet (figured out the overhead lights need to be on for the rear cabinet interior light to work), the front one has a switch on it.
Hope this is helpful. FYI: still some small QC issues with the new van, hoping to get back to dealer next week to get those fixed, but overall very happy with purchase.