I recently changed my two rear tires from the stock Potenzas to some BFGoodrich G-Force Sports (they are not the same as the G-Force KD/KDW).

I searched this board for anyone that had experience with them, but was unable to find anything. After looking at a few different options on Tire Rack, I found that these were one of the highest rated summer tires in the size I was looking for, so I decided to give them a whirl.

Keep in mind that there were quite a few factors that should also be considered:
1) I only replaced the rear tires which were OEM Potenzas
2) The front tires continue to be Michelin Pilot Sports
3) I went from a 235/50/17 to a 255/45/17

With that in mind, here is my review after 1000 miles (as compared with the Stock Potenzas):

-Dry Traction: feels slightly better.
-Wet Traction: feel marginally worse.
-Cornering: During hard cornering, the back end felt a little more stable and less likely to swing out (this could just be from having a slightly wider tire though)
-Stability: At highway speeds, the sidewall seems to have a little more flex and this translates into slightly more "rocking"
-Noise: considerably worse (even more noise than my snow tire setup)
-Ride comfort: Seems to be about the same as the Potenzas.
-Price: Excellent! $120 per tire at my local dealer.

All-in-all, various factors may have been adversely reflected in my impression, but these are tires that I was NOT impressed with. The OEM potenzas are bad enough, and these did not feel like an improvement at all. I will probably NOT buy these again.

 

Unfortunately choosing a tire is one of those decisions where you really get what you pay for.

 

I had the sports for about 1 month...sold them for the KD's. Nice to have them in front for slight understeer with KD's in back so there is not too much over steer.

 

Good review.. now put those on craigslist and try something else!

 

Seriously...I got these because they have a good tread rating, and I put 2500 miles on the Z every month. Well I guess it's time to do a bunch of burnouts.