Picked up mine in May. First ever BMW let alone a GS so I can't compare to previous years / models but got a few years of riding other bikes under my belt so here's hoping you find my thoughts useful.
Got it with the Dynamic and Premium packs.
ESA, quite like it and enjoy being able to adjust suspension on the move but not sure I'd miss it if it wasn't fitted. Then again I might....
ABS & Traction control have already saved my bacon in the first 6 weeks of ownership. Suicidal sheep on a couple of occasions but more significantly an airhead in a BMW 1 series pulled out in front of me and I think they might have been texting at the time....

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On my previous bikes the situation would have been very marginal, on the GS it all felt very calm so
Engine, still getting used to it truth be told. I find it quite vibey and pins and needles in hands after a couple of hours riding....and yes it might be that I'm holding the bars a bit too tightly but not sure as I've never had this problem before. As for fuel consumption, I'm lucky to get around 45 MPG, although I rarely get over 4th gear in general riding and I'm a fat bugger so must be me as a friend with a 2010 model tells me he gets 57 regularly.......

As for torque...not sure what the deal is, had a Triumph Tiger 955i and the engine on that felt smoother and torquier... I have been told that miles improve things.....
Test rode a 2009 model with a Remus can on it before buying the new'un and if anything thought it slightly smoother and comfier but went with the 2010 as there was only £1500 price difference.
Seat....I have to agree with the camp that find it uncomfortable......but I'm willing to give it a bit longer so we'll see.
Having said all of that...went for a ride with some mates, intending to ride as smoothly as possible and ended up leaving them a fair bit behind, not, I hasten to add, that I profess to be a riding God but more to do with it being one of the most confidence inspiring bikes I have ever ridden, tbh it kinda threw me how good it felt.
Build quality, again, my first beemer but so far I'm pleased.
Bit of a Tome....but hey........you asked..!