Ive used a few on the GTS (for various reasons) all of this is IMO of course and I tend to be ******* tyres!
Bridgestones - awful IMO, wear quickly and have OK grip in dry but absolutely terrifying in the wet.
P Zeros - noisy, wear quickly and average in the wet - great in the dry though. Don't suit the GTS but were great on the 360.
Michelin Pilot Sport - very odd as they dont seem to wear but grip like slicks in the dry, OK in the wet, seem to be better when cold! go figure. By far the best road tyres ive had on a car and suit the GTS perfectly.
Eagle F1 - on the 4200 Spyder and just right - they don't do the sizes for a GTS not sure about GT.
last xmas I think Miles noted that my GTS seemed to have a modicum more grip on the run to the pub - so thats a conversation to be had
Mind you Michelins don't come off well when you hit fork lift forks at 60