Just have to put up some good words for the beemer here. It's a great road machine! About as buzzy as a twin, very smooth for a single. Haven't tried the Dakar, got the GS, but I assume they're about the same with a bit less road-worthiness on the Dakar.
It's a bit down on the power compared to most any other bike of the same capacity(with more cylinders), but you don't need more than 50 ponies to climb montains. Torque is the key and it got plenty of that.
I had no problems blasting along with fireblades and gixxers in the Alps, it's definitely not a chore in the twisties! Only big open roads will give the higher powered machines an advantage and that's the sort of roads that's booooring.. Did a few thousand autobahn kilometers to get back and forth fast, no problem there either. But boring.
Have done some track days since then. It clearly shows how much more a rocket can do - on a track. In the real world they're mostly unable to leave me behind. Sure, they shoot off in a cloud of dust on the straights, but I always ride their their tail lights in the next set of twisties. The nimble, amply suspended and grunty bike is actually a big asset on any road of less than good standard(all fun roads in my book).
It's dead stable as a road machine, good enough for 10000km's in five weeks last summer without a single complain(with taller seat and windscreen). And you get the benefit of enjoying the gravel roads along with your XT friend. The standard GS is not as capable in the dirt as the Dakar, but it's more than good enough for some light off roading and in the right hand a worthy tool for most any adventure.
This may sound like a huge overstatement for a small bike, but I believe you can't go much wrong with the GS. Beginners and experts fall in love with it once they get used to the less than stellar straight line performance. It's not the best bike for any purpose, it's just so surprizingly capable of doing just about anything with graze.
I'd stick with the hornet if you love it, get the tiger if you like it better, but if you want a bike with no fuel consumption (550km's on the 17 liter tank), almost no maintenance, ability do just about anything, ABS brakes, good comfort etc etc - have a look at the GS.
No, I'm not sponsored or anything, just deeply in love with my bike! =)
Andreas / Norway
(some pics and stuff at http://www.bergenteknomafia.com/pics/mc/