I've owned my M8 for just over 3 weeks.
First week I noticed one *tiny* scratch on my lens. So I ordered Slickwraps Lens protector.
Took a few days to arrive ( as in UK - but still very quick delivery).
So I've had it on my phone for just over a week now. With the same handling/treatment as before. I do work in a sometimes dusty environment. But my previous Samsungs and Nexus have coped admirably in these conditions. Very well indeed, as it goes.
So, after one week and-a-bit with Slickwraps on I have this:
It is scratched to ****. And obviously creates somewhat imperfect images.
So sorry Slickwraps: Your product does not perform.
I'm ordering a tempered glass protector right about now...