Yes the Potenza RE050A is a Max Performance summer tire. Treadwear rating is 180 (100 equates to 7200 miles). So these are said to only last 12,960 miles in total. So if you are coming up on double that with these tires, I'd say it's time for a switch.
Actually, the stock 215/45/R18 RE050As (note that the MS3 did NOT come with the "Pole Position" variant, as was mentioned earlier) have a
140 UTQG treadwear rating...
Also, I don't know where you came up that "100 equates to 7200 miles" garbage, but that isn't how it works...
Each manufacturer pretty much has their own standard, and the numbers can only be used to compare across tires made by the same manufacturer (as has already been mentioned in this thread). The numbers simply represent relative wear, meaning that a 200 treadwear tire will theoretically last twice as long as a 100 treadwear tire made by the same manufacturer.
...and to those of you who say you'll have a hard time finding a better tire than the RE050A, you're simply not looking hard enough.
While it is a great summer-only tire, there are several that are much better, and even more that are "better" if you factor in cost.
Examples:
-Dunlop Direzza Z1 Star Spec
-Kumho Ecsta XS
-Nitto NT-05
-Falken Azenis RT-615
-Bridgestone RE-01 (discontinued)
-Bridgestone RE-11 (already mentioned)
-Hankook R-S3 (a reasonably new tire, but initial reviews lead me to believe that they would outperform the RE050A)
I've had personal experience with the Kumhos, Nittos, and Falkens above, and can say that without a doubt, they are better performing tires than the OEM RE050As.
I put about 10K mile on my RE050As before taking them off, but they still have a few thousand miles left in them. I rotated every 2500 miles, and kept them at around 34-36 psi (cold) throughout their use. They saw one long open-track weekend (a couple hundred HARD track miles on a relatively tight, braking-heavy circuit) and a couple of autocross events.
I've gotten similar mileage out of the Kumho XS and Nitto NT-05 on this car.
