I have a K12GT, a 58 reg which I bought in 2009 with 6,000 miles on the clock. It's now up to about 40,000 and it has never missed a beat in all that time.* Ive always had the extended warranty on the basis that if something does go wrong, it's going to be expensive, but I guess the £300+ each year since then would have paid for most things.
For long trips and touring, it is excellent. Solo ro two-up (and suspension is adjusted electronically) it is fast and comfortable. Im no speed merchant, but it'll sit at 90+ all day if you want, and still rush forward if you give it a handful. For twisty roads it is also pretty damn good, though I'm always conscious of the weight of the thing. I enjoy riding round country lanes with grass down the middle and it isn't very good for that! It isn't quite the most versatile bike I've owned - the R12GS I had immediately before the K12 would fill that category for me - but I have an F700GS for country lanes and a short commute into work.
Putting it into first gear gives an enormous great clunk, especially when it's hot, but it feels liek a solid clunk rather than a feeling of imminent breakage.
I have a slightly duff left knee and found it had a fairly cramped ridign position for your legs. Strange given the amout of room on the bike. I fitted some footpeg extender things which lower the pegs by about an inch. I can now get the pegs down which I couldn't before, so as well as being more comfortable, I am now a riding god!
Pillions tell me it is more comfortable than the RT on the back.
HOWEVER - for anything that doesn't involve lots of motorway miles or two up riding, I find myself using the GS.
*Though it has been back to the dealers for four new fuel gauge sensors. Or maybe five. All replaced within two years of the previous replacement, so free to me!
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