Lenses have new coating as of jan 2019!! i've been shooting mine for almost a year with no scratch! - Shield Sights Reflex Mini Red Dot Sight

Is this a go-to-war bomb-proof optic? No.
Will this work great for 99.9% of Concealed Carriers? Yes.

I find that the fact that it is so low makes me much faster with it than my Holosun 508T or RMR.
The fact that the window has NO tint and NO distortion (unlike the Holosun and RMR) means it's much easier to see darker targets on dark backgrounds and smaller, darker targets in any kind of non-optimal lighting condition.
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From what I understand, the ones prior to JAN 2019 scratched pretty easily (though Shield will replace the plastic for you for like $75, and now they offer glass too). Scratching was my biggest worry when I got mine here. However, after almost a year of shooting it on 2 guns, with at least 1K rounds, there's not a mark on it. I was anal about cleaning it after the first two trips to the range, but have since gotten to where I just blow it off with compressed air. I only wiped it down by rolling cotton-swabs and electric wd40 every few hundred rounds or few months carrying it now.