I'm an adventure bike noob, and I couldn't be more thrilled with the new 2013 F800GS that I just bought. It's been cold and snowy, but I've managed to put 2200 miles on it since I bought it 45 days ago. I've camped in the mountains on it twice, and done quite a few miles on snowy muddy fire roads. It'll go places that I'm not 100% comfortable going quite yet for sure. There are a lot of naysayers on the site with this weakness, or that weakness, but I'd say the F8 is pretty dang well rounded all in all. I guess it can't be all things to all people, but personally I think it's a great bike. I set out to buy the big GS, but after riding them both I couldn't get past how much of a pig the big bike felt like compared to the F8. After taking the F8 on some gnarly to me trails, I can't imagine how much work it would be to get the R12 to some of those same places. My F8 is already starting to develop some nice battle scars.
The dealership wasn't willing to negotiate much on price with me, but they did throw in a set of Vario cases for free. There are better cases out there to get, but the price on the ones I got was right for sure. I've laid the bike over on the Vario cases a couple of times and so far they've held up well. Listening to people on here talk, I'd have thought they would have broken in to a million pieces after the first minor scratch. Glad they didn't.
I'd say go for it, but the Farkle bug is going to bite for sure. The $'s will just keep slipping out of your wallet until you get the bike set up exactly like you want it.