I know a little about this because i went through the same dilemma before buying one of them.
The barbed wire is solid (proglide) as the razor is. They both have the same core, a thunderesc core (some wedge that makes it asymmetrical). They one difference is that the barbed is at 1500 grit polished, and the razor is 800 grit matte.
I bought a barbed wire. I dont remember the exact layout somewhere in the middle of the road in terms of strength. My barbed wire was squirty at best, to much reaction on dry and oil scared it to death. I didnt play with the surface to much so it might have helped but i was in the process of switching weights. Just my 2 cents, hope it could be of some use.
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