My background is Porsche racing and so I drive my standard road Porsche accordingly on track days.
Fantastic dry grip and handling. Tyres are progressive on the limit and don't suddenly loose grip. Even in the wet they are progressive at the limit.
The rear tyres are at the end of their life after about 3-4 track days, depending upon the track. I have had the sidewalls disintegrate and the tread lift, typically on the 4th track day, on 3 separate occasions. So now I throw them away after 3 track days: following a blow out at 250km/hr. So why do I continue to use them? Because they have the best dry grip and handling in the dry when compared to any other road legal tyre on the market.
Nb: The front tyres last about 50% longer than the rear tyres and don't give problems.

