Why would the PP be bigger? the numbers on the tires tell you how big they are, there are very small manufacturing differences between the brands that it doesn't matter, you have to see what size tire it is, by the numbers, and then see if it fits, compared to what you previously had. This holds true for mainly road use
Now if you want to go on the track mostly.... that's another story...
I personally prefer the stock Bridgestone BT016, had only good experiences with it and did a "few" laps on a track with them earlier this year and had no problems at all. But they are at the end now and need replaced... guess what I'm going to put on next??? :mrgreen: