Hey Tom, good to hear from you, my friend.
Some of the guys over at the K1600 forum have XR's, and are pretty happy.
I've seen what a well-ridden GS can do in the tight twisty stuff, where that long-travel suspension just soaks up all the pavement irregularities and gives you never-ending lean angles.
Think of this like a SuperSport/SuperMoto hybrid, and you start to get the idea.
Give me that agility and reduced weight with a smooth Inline-4 motor, and I'm interested. Add the normal BMW comfort features, cruise control, and alphabet soup (ASC, DTC, ABS, ESA, etc.) and I'm going for a test ride...
After my test ride:
Very light and flickable, love the upright seating and wide GS-style bars, tons of power (although expectedly a bit more revvy than my massive Slant/6 GTL), and lots of fun to ride quickly. Biggest downsides are the minimal wind protection, and chain drive maintenance.
If you want a GS with a smooth Inline-4 and all of the advanced BMW comfort and saefty features, then this is the bike for you...