Hope for ceramic cartridges?

[StellarTV]

Is there any hope for our phonos and Hi-Fis that use ceramic cartridges? I work on a lot of 50s and 60s equipment for people and the original cartridges are all starting to go south. I'm particularly dismayed that I've found many NOS ceramic cartridges to also be bad or intermittent, which is the exact issue with the ones that have been installed and in use, or even not used while installed in equipment for years...

So, there's a new ceramic stereo 1/2 mount cartridge available now... the Varco TN4B aka Pfahenstiel aka Empire... the two latter appear to be rebadged Varco carts. I'm curious if anyone else has experience using these carts? I have ordered these in bulk and have had mixed results using them... some of them, even though they are 'new' have intermittent output just like the old ones. One in particular, which I've been using in my home Hi-Fi; an early 60s Packard Bell, started out sounding great but now has intermittent output on both channels and shrill highs. What gives? More importantly, what is the solution here? Can't use old ones, and the Varcos are pretty much trash... but at $10 a pop is it worth complaining?