Richard, a sidecar riding R1100GS guy in outback Australia has one fitted to his bike. His bike is pretty much a rat bike but it goes like stink.
After he had done his second clutch by glazing the pressure plate side for the second time he heard about ceramic clutches from rally car people.
His clutch came from Sth Africa as far as I know. It may not be the Touratech one as I'm sure there is more than one manufacturer of this kind of product in the world and they would more than likely source theirs from Germany or similiar.
I know that he had to change all 3 plates and bits and seals as well (probably because he found stuffed stuff). It caused a bit of consternation at first as it apparently slipped because it was a tight fit. But now that it is run in after a very long run in period of about 3,000 to 5,000 Klm's I last heard that it's the Bees Knees!
As he rides and lives in sand hill territory and his shopping is a round trip of 600 Klm's or a couple of hours in an aeroplane, the bike does get a terrible caning when he uses it.
I last spoke to him in October last year and he had had the clutch in for about 1 year then. He was quite chuffed with it but as the clutch didn't break now, the subframe and the aluminium seat spar had broken badly in several places as a result of the caning in the bush it received.
I think the cost would have to one factor and the availability when one needs a new clutch plate is another factor, after all I don't think there are many sitting on workshop shelves and if my clutch goes I want the bike back on the road ASAP instead of waiting a couple of months for a Ceramic job.
Mick.