One of the guys there yesterday, was an ex-tyre tech for Pirelli. He know owns BikeTek who you see at MSV, Hottrax and Focus track days. Think his name was Dave?? Not sure.
He said, that a good set of tyres should do 6 heat cycles but no more. He said any more than than and you treading on thin ice. He said that Racetecs do go off a little quicker and its between 4-6 cycles.
He noticed I had Corsa III's on, and he swears by them. Reckons they are a phenomonal tyre. I have to say, so far, I agree. Looking forward to the summer to really give em some stick on the road. Another comment he made, was that he had some feedback from a few fast boys at track days about the new Avon Viper Extreme who said they are incredible. Apparently they are formidable force in the tyre war?!