@vk6flab @KA7O @BrucePerens_K6BP 500 matings is not at all long for test equipment. I probably put a dozen or two cycles on my NanoVNA when building a linked dipole for 10/15/20/30.
I've been noticing some sloppiness after a few years' use, so I just put portsavers on it a couple months ago. Hopefully they work, because replacing those giant SMAs sucks enough that I'd probably just get a new one and experiment on this unit.