I'd call the pro2 tire 'broken in'. Put in on the back. Pump it up to max psi for low rr. When you say the maxxis tires are 'crap', how are they crap? If they tend to bounce around turns and scare the crap out of you...reduce the pressure in the front. If you have lots of climbing to contend with and tend to stand and really rock the bike, more pressure in the front. You're putting more weight on the front with that style of climbing, so higher pressure in the front should result in less rr. I'd 'guess' that sprinting hard out of the saddle is similar to climbing out of the saddle with respect to load on the front tire, so if you think it's gonna come down to a sprint...more air in the front.