Had my PS4S a week now and I'm impressed. They grip much better than the old Pirellis, even when they were nearly new. I've not had any wheelspin or tramping neither has the traction control light come on and it has been wet and cold. I'd have had all 3 regularly ibefore changing 
Only annoyance is some marks where the wheels were clamped for tyre removal/refitting. Checked with the garage, and they are very good been going there for years, and they said they were as careful as they could be, no marks on the faces, but couldn't entirely avoid some marking as the machine had to be able to grip. Anyone else noticed this? It is right at the rear of the barrels so very difficult to see so I'm not too annoyed but certainly disappointed after all the efforts I have put in to keep them tidy. 
If they do it the easy way then use they will mark the wheel but if the use it the harder way then there should be no marking. The machine should have two ways to grip the wheel, one where it holds the inside rim edge which will leave no marks that can be seen without taking the wheel off and looking at where the tyre and rim meet and even then should be very hard to notice.
The other way is where the jaws of the machine hold the wheel from the inside of the barrel and that will leave 4 marks with each one having 3 or 4 lines. That's what the dealer done to two of my new wheels wheels so I rejected them.
Today was the first time I've driven the car with the PS4's and the difference was quite startling. I have done a few brake tests before I had the PS4's fitted but still need to do it with the Michelin's but waiting until the temperature is the same.
