ive got a buddy that runs 33X13.50 LTBs.
he got them ballanced at a shop for about 10 bucks each, and it didn't do a thing. over 30 miles an hour the jeep felt like it was flying apart. i worked at a tire shop, so i told him to bring them by, and rebalance them for him. most average tires i saw during the day needed 2-3 ounces inside/outside of a wheel to balance with a "bad" tire needing 6-7 ounces, and those were usually larger truck all terrains. i threw one of the LTBs on the balancer and got a 33 ounce reading, thought that couldn't be right, and tried it again. same deal, with all 4 tires.
so we headed to walmart got some BBs, put 10 ounces in each tire, and its much better. isn't perfect, but its definately driveable.
plan on balancing my 38 inch SXs the same way. im not hoping for a miracle though, with a bias tire that large, just something that can get me to the trail and back