That's a tough one.
Anyone ever broken one on the trail?
I've run 35x15.5 swampers on an Soa 60 for years and never broken one. Countless trips over the 'Con, etc.
Now after saying that, I'll break one on my current sua 60!
Why not keep them and when you start running out of room or get too heavy, retire them to the "spares shelf" in the garage.