Being 3d printed, they are not going to be as strong as the original nylon. If you're building a runner, I would use original parts, or run dual rear shocks. The cost to print them in Aluminum would be about $150! So not really worth it, as you can find an original set in aluminum for that. I did machine some reproduction sets in aluminum a few years ago, but was not able to make many and don't have access to the equipment anymore.