I've had great success with both. It's kind of a personal preference thing because they both work great off highway. 10.50s have a little less rolling and wind resistance and feel like a much smaller tire than they actually are on the highway. the 10.50 rub less and can be used on a stock rim, not a big deal for most guys since we usually run wider than stock wheels anyway. Narrow tires work better in some kinds of snow but the 12.50 work well too if you run single diget psi. There is no right answer...
