Warmer? I think the Corrugates. But really, if you're looking for a warm pant these two aren't the best choices. Both good pants overall and with merino long underwear would be great for active use in most seasons as long as it's not pouring freezing rain.
In my opinion, I think the cut and stitching is better on the Prana Zions over the corrugates.
I think the corrugates would be warmer. And I definitely think they would be tougher in that terrain. They are about bombproof as far as tearing them. I wore mine in Mexico this spring and I purposely walked through the nasty brush and slid around in rocks just to test them. Still going strong, no tearing at all.
Where are you hunting in AZ? The southern part in the Sonoran desert isn't very cold in the winter time. In addition the pants you described are going to get ripped up in the cat claw, mesquite and cactus. If you are hunting the northern regions your pants choices are fine.