Have you found the guns to fail to cycle in live fire when they don't return by VSRTBT or rather when do they start to fail? I have been using the 13# with a well worn factory striker spring that fails the test, but has not had issues during live fire. I plan to replace the striker spring for next season and want to anticipate any issues (and save on shipping for a damn spring ).
I replace the 13#ers often and general keep my match gun well lubed.