The PZero's I had rode really well.. maybe the GT Coupe weight? I do love the ride of the Michelin Pilot PS2's I was skeptical at first but even as a larger width lower profile tire it rides good and I'll consider picking up a new set when these wear out.

 

Rupp, I just put on the Goodyear Comfortreds on my Mustang. I have about 2000 miles on them. They are way smoother and quieter than the stock B.F. Goodrich KDWS tires that came on my car. I read all of the reviews on tirerack.com. Lots of people complaining about tire wear too early, can't balance them and a loss of a couple of gallons of mpg.

I haven't had them long enough to confirm any of that except the ride and comfort. They are nice in that respect and that's what I bought them for. I don't rip on my car very much so I expect to get at least 50,000 miles on the tire. They are rated for 80,000 but I don't expect that. If I get it, great. If you want a comfy quiet tire, this is it. I have 18" rims so I bought 235/55/18s. They are a little taller than the original tires and I think it's thrown off the speed slightly and odometer a little more. I am going to get the Fuego tuner from Granatelli when they come out with a tune for the 08'. They don't have one now but working on it. They said Ford keeps changing their computers each year and they have to update the tunes. I am hoping I can get the speedometer and odometer back on track with that. Hope this info helps.

 

Again, comfortreds are NOT meant on a GT. and expect as mentioned 50k on the 80k tire on these cars.
good tire for a v6 thats all about ride comfort, thats it.

 

are you on crack man? the 555 is nearly a semi slick drag radial. they ride like steamrollers.

 

Anyway goodyear comfortread in 215/65/17 should be GREAT for ride comfort. the tire size is important too. also, it may cost you more in the end because they wear quicker but nothing is free.

 

Try Michelin

 

That size fits 6-7.5" rims. I believe you have a 8.5" rim.
Just stick with the OE size 235/55/17