| As a complete Diablo convert (the ordinary ones, not the Corsas) I have just found the only flaw with them.
Having done two trackdays and about 4K miles on a set, I have nothing but praise for their grip and the mileage you can squeeze out of them.
But...when they start to go off, they go off very quickly and get all squirmy once they're worn. And, they seem to be worn out and squirmy when visually they seem to have a reasonable amount of tread left.
After the DSC trackday at Rockingham, they got a bit blue round the edges, but still seemed to have a couple of mm wear left. I've done a few rideouts since then and went out on Sunday with tyres that seemed to have another 5-600 miles on them, just enough for the last ride before some serious fettling takes place. Got to the pub at the end of the ride out (150-ish miles) and they were ragged.
Brilliant tyres, but change them when there looks like there's another thousand miles left on them | 
Jools
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