For the last couple of years I've been doing 15-20 track days per year, and as you can imagine I've got through my fair share of rubber. With Cayman (I've had the Cayman for 14 months) I decided I couldn't be bothered with the hassle of a 2nd/3rd set of wheels (as I did with my previous track car), and because my car gets used on the road (NC500, Wales touring etc) and at all times of the year (summer & winter), I decided to go with a tyre that was capable of shedding some water. I thought my only real choice was the MPS4S and duly ordered some, but unfortunately Michelin had run out in Europe along with Cup 2s! I therefore looked around at some alternatives and found the newly released Goodyear Eagle F1 Supersport and decided to give it a try (at this point there weren't any reviews out but I really needed some tyres). To cut a long story short they have been excellent and lasted very well considering the abuse they received. The first set only failed because I hadn't put any adjustable arms on the front of the car and wore the shoulders out. Now the car has some proper camber the car so SS give fantastic grip in all weather, they even perform well on wet trackdays.
Next year I will no doubt be very tempted by the SS R, but the appeal of the SS for me is it's performance Vs the price, which was at least £100 cheaper than the MPS4S for 4 tyres, and the Cup 2s were around £250-£300 more last time I checked.
p.s My car is running the Spyder wheels (19')