Since I'm no longer an F6B owner, I was refraining from posting. Since somebody else already mentioned the BMW, I'll chime in as well. I moved on from the F6B to a BMW r1200rt. The r1200rt by far has the best suspension I've tried on a motorcycle.
I miss the smooth F6B engine and I'd argue that the F6B is a little more stable on the freeway but believe the r1200rt wins all other categories easily. The center of gravity is fairly low, it weighs 200 lbs less, has good enough torque everywhere, handles awesomely, and has fantastic suspension. Truly the first bike that I think is great on the highway, on the twisties, and in the garage. I will soon own only one motorcycle for the first time in many years. I know i sound like a BMW fanboy but believe me, I was anti BMW anything until I owned this motorcycle.
If you're looking for better suspension or a lighter replacement for the gl1800 platform, give the r1200 platform a try. It may take a bit to get used to the ugly motor and ugly sounds but the performance is fantastic.