It's not bad at all if you have another bike to ride. I'll admit, if all I had was one bike, and it was a straight line dragger and nothing else, I would probably get bored with it after the first year and part it out. But, that's why you have a dragger....and a play bike
Brad, if this guy is legit and you feel comfortable with this deal, I say go for it. Not very often you have someone willing to give you 10 G's for a banshee; hell, that alone says something about your bike
Just don't sell it before the LS ride, or at least bring it with you so I can drool over it in person