Baph

I'm running PR2's as well, and I know a couple of guys that went touring on thou's around Europe. The sets of PR2's they used managed 6k quite easily.

Personally, I prefer the PR2's to the Z6's. I'm with Dicky Ticker, I run at 36/42 as well. At first it feels like you've got bricks on at low speed, but you quickly get used to it, and I find there's more feedback at the higher pressures.