I've had a 2015 x28 (non-DHP) for a couple of weeks now, but my only pre-2015 experience was a couple of quick test drives on freeway and city streets (no backroads). They didn't feel any different to me.
I'm coming from a WRX and am suffering a little bit from "I wish I had DHP" syndrome. I didn't know about it when I bought the car (had no plans to buy a BMW, test drove on a whim). Actually I had no issues with the handling until I found out I could have had more
It's actually pretty fun in sport mode when the steering damping kicks in, but I'll probably upgrade to progressive springs and stiffer dampers at some point. It would be nice if BMW made the euro sports suspension available as an after purchase upgrade. Anyone tried buying the OEM sports suspension parts and swapping?
*side note - the best suspension I felt out of everything I test drove was the Tiguan R-Line. Unfortunately it didn't have enough passing power.