Now have PR4 GT F & R, my impressions thus far, i.e. 1000 Klms far. Came from PR2's.
Half the road noise from the front.
No brake vibration from the front. On removal of the PR2, we found that the tread has a lip on centre for each groove which sloped back to the next groove. I am not heavy on the brakes, pads last 40k+
More predictable cornering, will reassess after more K's.
Softer ride, even with 44 psi and solo, again will reassess after more K's
Much more stable at high speed, in fact best stability so far compared to past tyres.
A group of 4 riders including me traversed a white chevron in the rain and all slipped. The claim that the PR4 is better in the wet applies to braking distance only, it is in the design of the tread. Does not do much more for sideways movement than before.