One thing that has to be considered for those reading the mini-comparo. I have been riding the ST1300 for the last 7 years now, and have over 75,000 miles between my two ST1300s. I've also ridden an SV650 for 1-2k in the last 1.5 years. So, while I have a little non-STeed experience in recent years, my M/C senses are all tuned to the ST1300. Somebody who has spent the last 7 years exclusively riding a WR250 would certainly have a different perspective.
Comparing the F800GS to the Tiger 800XC :
Comfort - The Tiger wins hands down. BMW apparently got the seat engineer from KTM who was fired because he used the wrong type of wood for their plank seats. BMW isn't picky about what type of wood is used in the plank, because they cover the plank with a thin layer of vinyl before putting it on the bike. So covered, it is a quite nice looking plank. Yet, still a plank.
Engine - The F800GS (hereafter "FGS") has a nice engine, revs were consistently lower than the Tigger's at the same speed, no surprise there. However, the Tigger's engine was much smoother. Yes, coming off an ST we likely have really high standards of "smooth" from an engine. Nonetheless, the FGS was buzzy compared to the Tigger, noticeably so.
Switchgear - gackkkkk! IF I owned only one bike, I could get used to the freaky BMW switchgear. Catch is, this homeboy don't do just one bike. For that reason, from a safety standpoint alone, the BMW switchgear almost disqualifies the bike from my consideration. Add in the fact that the switchgear just isn't as conveniently located, and mongo blech, blech, blech.
Transmissions - Poe-tay-toe, Poe-tah-toe. Both are very nice.
Handling - Pretty close, although the Tigger felt a little more stable to me. Both much more "skittish" than the ST, but I expect that's primarily an artifact of my familiarity with the ST.
Clocks - Gasoline, Petrol. Same same only different that makes no difference. Neither has my preference of analog tach and analog speedo.
Mirrors - Tigger's are slightly better, but the FGS's are also very good.
Wind Protection - Tigger's may be a smidge better, but both are much better than I expected from 'em.
Lighting - no idea, daylight tests.
Carrying capacity and pillion - didna test either on either bike.
Brakes - good on both. Different from the ST, more dive.
Suspension - the Tigger is a little bit plusher. Neither bike was actually set up for me, so my take on the suspension may not be terribly accurate.
Looks - I prefer the Tigger. If the FGS didn't have the asymmetrical headlights, it would be a wash between 'em.
I also tested the Bonneville SE, and while a Bonnie will remain on my Lottery List, one isn't going to be my next bike. Simply put, the seat is too low and the seat to peg distance isn't enough. I really want maximized leg extension, and the Bonnie seems to have less than my SV650! Other than that, 'tis a schweeeeet mellow ride, and the Bonnie SE that I rode has proper clocks!
The upshot: If I had the $$$ in my pocket, I would be making a deal for a Tiger 800XC. If the Tigger was half again the price of the FGS, I'd get the FGS. Barring a huge price differential though, the Tigger is for me. So now I think I'll wander over to Triumph's site and spec one out....