I used to take a 2x4 about 5ft long, and drill nuts and bolts onto both sides. These are a vast improvement, and wont eat my tires. As a commuters too, it will be exceptionally useful. As a softroaders tool, it will be my initial go-to option for helping myself/others out. I think for my level of use, they will last forever, until I move back home, and I tease the -40* temperature limitation. Sand, snow, ice, mud... I think it will serve its purpose with glorious colors. What I am now trying to figure out, is how to tether it, so I can drag them with me until it is safe to stop after a recovery.
The durability would probably be compromised if you had to use it on seriously rocky/hard terrain. It flexes, but if you take a side glance at the units, they are actually pretty thin between the ridges, so take car not to have anything sharp fly between them while you load em down.