Thought I'd report back a year after swapping my 2004 R1200GS for a 2004 KTM 950 Adventure S (in superior GO!!!! blue & orange livery).
Stats so far (approximate!)
Total miles on the bike: 22k
Miles done by me in a year: 10k
Services: 1 big one (valves etc) £300, 1 small one £140ish
Consumables: Tyres: 1 rear Scorpion, front still OK, £80 ish. New chain & sprockets approx £140 - sprockets were fine but went for a 16 tooth front for more go!!!!
What's gone wrong:
Clutch slave cylinder gave out. Replaced by me for £80. Fairly common issue by all accounts. Suggest some preventative maintenance if you are nearing 20k miles, or buy the Evoluzione one which is better. Had the same issue on my Aprilia RSV.
Rear brake. Master cylinder replaced under warranty (3 year warranty) at last service. There is a technical service bulletin on the rear brake so take your bike in and they'll put a new one on for you. Had the same issue on my Aprilia RSV as well!
Occasional engine stall when hot - traced to kinked vent hose and sorted at service.
Totally unbiased owner's opinion
The KTM is a more "dynamic" bike than the GS. By this I mean that it is more involving, responsive, feels faster. The small amount of off-roading I've done shows it to be superior to the GS from a suspension and handling perspective and it feels easier to ride, but to be honest I've got nowhere near testing it "properly" off road.
The KTM definitely attracts more attention, being rather massive and with GO!!!!! written down the side in big letters. Lots of grins and thumbs-up from people. It is a pretty monstrous bit of kit and lots of people comment on how purposeful it looks. Ugly as sin though. The GS is quite anonymous by comparison and there's a lot of them about.
With carbs, the fuelling is just superb. No jerkiness on/off throttle, putting the power on is sublime. Fuel injection is pants.
Tank range isn't as good - I get about 185 miles compared to 230 with the GS. The KTM has a 22l tank (same as the GS??).
The KTM brakes aren't as powerful as the GS's servo assisted ones. This is a drawback but you just need to squeeze the lever harder. It'd be interesting to see how much quicker the GS stops. However, I've got more confidence in the KTM brakes than the GS ones having had 2 servo failures on the GS.
It's an easier bike to work on in some respects. Anything drivetrain related is simple as anything. Suspension, electical etc is also easy. Oil changes are a bit fiddly if you do the whole thing with cleaning of both oil screens, but this only really needs to be done once a year in major services. Valve adjustment is much harder compared to the sticky-out bits the GS has.
Build quality seems really very good. The bike cleans up really well. Just got a few spokes that are going a little with all the salt, but they polish up well. All other kit is pristine.
Things I miss about the GS are the smoothness and saddle comfort. Sometimes the KTM is a bit too much (cold winter morning) and I think a GS might be better. I've got heated grips on it, so it's not that, but it's more to do with the amount of feedback (noise, vibes, suspension movement) coming from the KTM being much larger than that of the GS which can be a bit much if you just want a quiet life. On the other hand, this is a positive of the KTM the rest of the time when it is really involving. Also, the GS saddle is more comfy than the KTM - I dont have a gel seat so the one I've got is a bit hard. A tour to the Pyrenees in a couple of weeks will reveal all I've no doubt.
Other stuff - all the bits I had on my GS are now on the KTM. The Autocom is wired in, 2-way radio sorted, ipod & phone rigged, GPS on & powered, heated grips sorted, heated vest power available.
Hope this is helpful to someone.
Cheers
Tobers
Stats so far (approximate!)
Total miles on the bike: 22k
Miles done by me in a year: 10k
Services: 1 big one (valves etc) £300, 1 small one £140ish
Consumables: Tyres: 1 rear Scorpion, front still OK, £80 ish. New chain & sprockets approx £140 - sprockets were fine but went for a 16 tooth front for more go!!!!
What's gone wrong:
Clutch slave cylinder gave out. Replaced by me for £80. Fairly common issue by all accounts. Suggest some preventative maintenance if you are nearing 20k miles, or buy the Evoluzione one which is better. Had the same issue on my Aprilia RSV.
Rear brake. Master cylinder replaced under warranty (3 year warranty) at last service. There is a technical service bulletin on the rear brake so take your bike in and they'll put a new one on for you. Had the same issue on my Aprilia RSV as well!
Occasional engine stall when hot - traced to kinked vent hose and sorted at service.
Totally unbiased owner's opinion

The KTM is a more "dynamic" bike than the GS. By this I mean that it is more involving, responsive, feels faster. The small amount of off-roading I've done shows it to be superior to the GS from a suspension and handling perspective and it feels easier to ride, but to be honest I've got nowhere near testing it "properly" off road.
The KTM definitely attracts more attention, being rather massive and with GO!!!!! written down the side in big letters. Lots of grins and thumbs-up from people. It is a pretty monstrous bit of kit and lots of people comment on how purposeful it looks. Ugly as sin though. The GS is quite anonymous by comparison and there's a lot of them about.
With carbs, the fuelling is just superb. No jerkiness on/off throttle, putting the power on is sublime. Fuel injection is pants.
Tank range isn't as good - I get about 185 miles compared to 230 with the GS. The KTM has a 22l tank (same as the GS??).
The KTM brakes aren't as powerful as the GS's servo assisted ones. This is a drawback but you just need to squeeze the lever harder. It'd be interesting to see how much quicker the GS stops. However, I've got more confidence in the KTM brakes than the GS ones having had 2 servo failures on the GS.
It's an easier bike to work on in some respects. Anything drivetrain related is simple as anything. Suspension, electical etc is also easy. Oil changes are a bit fiddly if you do the whole thing with cleaning of both oil screens, but this only really needs to be done once a year in major services. Valve adjustment is much harder compared to the sticky-out bits the GS has.
Build quality seems really very good. The bike cleans up really well. Just got a few spokes that are going a little with all the salt, but they polish up well. All other kit is pristine.
Things I miss about the GS are the smoothness and saddle comfort. Sometimes the KTM is a bit too much (cold winter morning) and I think a GS might be better. I've got heated grips on it, so it's not that, but it's more to do with the amount of feedback (noise, vibes, suspension movement) coming from the KTM being much larger than that of the GS which can be a bit much if you just want a quiet life. On the other hand, this is a positive of the KTM the rest of the time when it is really involving. Also, the GS saddle is more comfy than the KTM - I dont have a gel seat so the one I've got is a bit hard. A tour to the Pyrenees in a couple of weeks will reveal all I've no doubt.
Other stuff - all the bits I had on my GS are now on the KTM. The Autocom is wired in, 2-way radio sorted, ipod & phone rigged, GPS on & powered, heated grips sorted, heated vest power available.
Hope this is helpful to someone.
Cheers
Tobers
) so when the Scorps wear out I'm changing to Avon AM26 Roadrunners.