Hello Omaro,
Z1 Compact uses Dragontrail glass which is as strong as gorilla glass. The glas does however not come with a oleophobic coating
As an answer to your first question there's no glass which is 100% scratchproof. Minerals can scratch pretty much any types of glass, and by minerals I'm talking about sand, stones etc etc.
The reason why most people wants to remove the preinstalled antishatterfilm is due to that it collects dust, fingerprints and its very easy to scratch. It's not recommended to remove it if you're not planning to apply a oleophobic coating on top of the glass.
Hope my answer cleared any doubts,
DevStaff
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