In that GRM comparison, there are a couple things worth noting:
- As ZM2 pointed out, there is the fact that the RE-71RS could be better for lighter cars given the test was on a Miata.
- The RT660 runs wider so they compared a size smaller in the RT660 to try and compensate for this.
- The RT660 they tested was at full tread and that tire does get faster as the tread depth becomes shallower. They stated a worn RT660 ran a similar time to the fastest time of the new Bridgestone during a previous test.
showed the Bridgestone slower than it's competitors in the dry on it's [short] test track, but most of us don't drive on tracks that take under 30s to lap.
If I can get similar longevity out of the RE-71RS as I did with the RT660, I will continue to use them. I think their drivability, wet-weather prowess, and characteristics outweigh the cons of them being easier to heat soak and higher costs.