I haven't tried a 'non-stick' grinder before, but doing some quick reading now it seems they use a sacrificial non-stick coating. No idea if this is something like Teflon, or a ceramic coating - but either way I would assume that it would degrade over time and may affect longevity.
It's worth looking into what exactly the non-stick coating is, and making sure it's not something toxic in itself. If not, it may be as bad as plastic grinders for putting unwanted particles in your grind over time.
I've used the same ~£5 zinc alloy grinder for over 10 years (with the pollen sieve detached), every 6 months or so I scrape it out, then douse in IPA to remove all the pollen from in-between the threads.