I have to disagree with the above statements.
I bought a full set of razr2's and i think they suck. Granted your whole setup will come into play when your looking for traction. power,suspension gearing etc.
But I would spin the shit out of razr2's, they wouldnt hook for me, On hills in PA, forget it, I would just dig in.
On hard pack surfaces, they are okay, but on shoft terrain they are horrible in my opinion.
The fronts are a great tires. Meaty and tough as nails.
I run a 22 in the rear similiar to the vampires and they are gangsta, they are made by razr.
But it all depends on te terrain you will be riding.
In the pic, they are about 70% thread and still hook better than my razr when they where brand new