Part of the reason I think it seems to have better grip and longer wear is the higher profile and therefore slightly higher gearing which means it is more inclined to maintain traction under similar riding conditions than Metz or Avon. That's not to say it's necessarily a grippier tyre, although I do think it is anyway.
I'm very happy with the way it hangs on and I actually like to be able to feel it break traction under hard acceleration when the mood takes me. When it does it feels very controlled. I also have much more confidence in the wet than with other tyres.
I wouldn't call it a wonder tyre but having tried a couple each of Metz and Avon it's certainly the best of the bunch by a big margin. I have close to 7,000km on my second Bridgestone and have to say I haven't noticed any deterioration in performance at all. Hoping to get to 10,000km as I did with my first one.