The F800R is a polarising bike, some don't like the band of vibration when you're having fun at 5K, but most use around city/freeway you're under that anyway. Good luggage options on it as well. The NC is a -nice- bike, but thats just it...
F8's got a -little- bit of fun in it, just digging for it at times isn't that hard!
Setting mine up for touring and I've got the options pack of computer, tyre pressure and heated bars. Unless he really wants the BMW, I wouldn't disagree the cost would buy bigger in another brand.
Fuelling on the F8 like the NC is really frugal. Handling is sharp. After a GSA, it's like a knife in traffic!
Check out F800riders.org, there's little on the F8 that really springs up as a common problem with the post 08's
Vibration band is small, but you're not always riding around the 5-6K zone, some really notice it, I was never aware until I started hearing about it. Like most things you get used to it.
End of the day if HE likes it, he'll buy it, you only live once!