Tom, you know the guy and his son that ended up putting my tires on the rims showed me what and why people are afraid of the explosions. They didn't use any type of cage, no chains, nothing. The pics I've seen of the explosions look deadly.
He inspected each and every ring that goes on the outside of the split-rim. And I couldn't believe how hard they were beating on the rims, they were pounding the p!$$ out of them with a large sledge and pry bars. The problem he explained is that the rings tend to crack as they get old, and if they have started to crack, that's dangerous. If not, they are held together as designed. Before he put any air in them, he made certain everything was put together properly, split-ring double checked, etc...both him and his son worked the p!$$ out of those tires and rims.
With all that said (aren't I a wordy puke?). split-rims take bias ply tires in all cases, AFAIK, and bias ply are better for trucks and trailers that are not driven regularly as the steel belts in the radials tend to rot/rust when they just sit. If you drive them frequently, no worries, but larger trucks and trailers have a tendency to sit around in one spot for long periods. Many, many, many people will tell you they walked out one day and the radial tire had literally blew apart into shreds, just sitting there.
As a case in point, I don't imagine your drive your 3-ton truck too often, but I could be wrong...
I have years of adventures with that old truck. I bought it from a rancher whose son was the Governor of Nevada at the time. Just to be on that ranch was an adventure. I injured myself there and his other son had to drive me to the hospital. 
