I prefter the Big Horns personally, but they are teeming with road hunters, so if you go there be sure to get off the beaten path a bit to give yourself a chance at getting a decent deer. There are big deer everywhere in Wyoming. It's just a matter of putting in the time and effort to find them or getting lucky and running across one of them. My buddy tagged a really nice whitetail in the Black Hills last year, and I also saw many 4x4 and 5x5 mulies in the Big Horns while I was archery hunting for elk the year before last. So either place is a safe bet. Just make your decision based upon how far you want to drive, the kind of land you want to hunt, and if you still can't decide just flip a coin.