They are 195/50/15's on the wheels. Compared to the 16's that I had on the Cup they altered the speedo by about 2mph @90, so they don't knock it out by a great deal.
I can try and get decent pictures for you when I get back home this evening hopefully.
Sidewall wear is on 3 of the 4 tyres but only scrubbing as every trackday I did with them (3) I put a different wheel on the front nearside to even the wear.
I'd estimate you'd get another couple of trackdays out of them, or a few thousand road miles. The advantage of 15's though is 195/50 tyres are dirt cheap - a decent brand would be £30.
I mainly used them as winter wheels to save the Turinis.