One other point : the 2014+ will have electric-assist steering, not hydraulic. For me, it is all a big deal - recently got 2013 335 for my wife, and not thrilled at all. So i am trying to stretch out avoid going into that for as long as possible.
Hers : 2015 328xi MSport Silver/Red
His : 2016 X3 35i MSport Silver/Mocha