I will do some updates. I've made some changes during the last year.
Regarding balancing 40s. The Xterrains and Walker Evans beadlocks didn't require much weight. So, when I swapped the tires over to ATX Slab beadlocks with a 5x5.5" bolt pattern to run on my Dana 60s, I didn't have them balanced. Between 72-75 mph is when I start to notice that they are not balanced. For me, that is fine. When I go very long distances, I trailer it anyway.
Now, on a less expensive wheel, no balancing could be a bigger problem. Also, other tire brands sometimes require more weight. I don't think a Super Swamper or Goodyear MTR 40" tire on a steel wheel would be smooth at 70 mph with no balancing.