You will love the car. On to my 4th Mini and my wife has a Countryman and the F56 Cooper D is the best by far. When you get a few miles on the car the engine will loosen up and its just a fantastic engine. I had a SD loan car for 2 days recently and despite another 500cc and 60 odd horsepower I was surprised it didn't seen that much faster than my D. My D is also much quieter and refined and more economical. Amazing for a 1.5cc 3 cylinder engine.
I really am enjoying it so far, my wife has a 2013 Mini Cooper and as lovely as it is I can't believe how much nicer the new model is - she won't mind me saying that as she has a VO Cooper D arriving at the end of the month to replace hers!