Well, the vibram sole on the back wore through to the next layer and they really aren't the sort of shoes you can resole. I noticed it because it threw my gait off enough that I started to get a little knee trouble.
So, I picked up some shoes to just try out another type.
Got some New Balance 410 v4 Trail Runners (they were available in my size and I'm in the middle of travel).
First thing I discover is that while they are sold all over (Dicks, Amazon, etc.; e.g.
https://www.amazon.com/New-Balance-M.../dp/B00OQ1RLZ6), they aren't listed on the New Balance website. Variations of them are sold as 412, etc. as well.
It was weird to realize that there are now so many trail runners that they drop in and disappear without a splash.
I'll know more about how I feel about them after a few hundred miles, but it was strange.