In reply to neuromancer:
> (In reply to Got a job rob)
>
> The difference between a top end tyre and a cheaper one is maybe at most 5-10% traction, hugely surface dependant.
>
> Much more important is the choice of tread, pressure, and going tubeless so you can run 20-25psi.
I had a set of Continental MountainKing/X King UST tyres that came with my bike. (They are the cheapo made in China compound) run at 20/35PSI. I changed them for Conti Rubber Queens (the black Chilli ones) also run at around 20/25PSI. The difference is absolute night and day especially on anything remotely wet. The MKs would slide around all over the place, yet the RQs allow me to climb up off-camber wet roots as if they aren't there.
I'd say the grip level difference is equivalent to the difference in using trainers vs climbing shoes around 50-60% (and the conti MKs are a good tread shape - just make sure you get the black chillis)