Heh, its funny, whenever I see a video of an American with glasses, they don't have a reflective coating. I guess its too expensive over there. I have glasses which have reflective coating and photochromic coating. They're also made of titanium. Very light, despite being -4 or so. My wife has even worse than -4, and she enjoys the same. They're a tad more expensive, yes, and eventually the coating goes bad which with proper usage can be postponed for years (e.g. wear real sunglasses on beach).

Do they shatter when you drop them?

They might if you drop them hard enough, but I've dropped glass lenses numerous times and I've never had them shatter on me. Probably helps to have a sturdy frame with barrel hinges, too: https://shop.shuron.com/shop/sidewinder/