I too considered the K1600 before buying my F6B. A great dealer let me take one out for a 50 mile test ride. A very impressive bike it is. The I-6 engine is somewhat similar to Honda's flat sixes, smooth with a broad powerband. The BMW has more top end power though the Honda seems to have a bit more at the low end. I loved the electric windshield -- you could get perfect coverage with the touch of a button.

The styling didn't do much for me, but that wasn't the deal breaker. I talked to some owners with nightmarish stories about maintenance and reliability. One guy had his water pump replaced several times. An oil change is a real PITA. The fancy electronics were buggy. The Honda (except for the air cleaner) looked like a lot less work, and cost about half. I haven't had any regrets.