I just added an 2015 BMW F800GT to the garage. I have been watching the bike since introduction in 2013. Since I am old, short, short coupled, T-rex arms ... etc, there are few bikes that fit my requirements. YMMV. I found a deal that I couldn't pass up. My view is that the increased cost of parts is offset by a three year warranty vs others one year. I can't get NT parts on hand from any one of the three Honda dealers in town. They order them.
I have ridden the GT twice for 30 miles each. I really like it so far. Break in is harder than one might think, vary speeds and keep revs below 5,000. My early impressions are:
Pros: F800GT vs NT700
GT is 100 lbs lighter, 20-25 more HP, lower CG, 6 speed
Great HP and Torque range, very responsive, belt drive is very smooth
GT is light and easy to move at rest and any speed.
One inch high gear indicator is nice.
Cons:
NT has a better windshield and mirrors seem to have a better field of vision.
NT has better wx protection but GT has better aerodynamics than expected
NT - 5 gal tank vs GT 4 gal (GT is suppose to get better mileage but ... ?)
F800GT - 60 mph - 3400 rpm, 70 mph - 4000 rpm (8,500 rpm max)