For the last time these are not laser engraved. They are laser etched. Laser etching is a superficial process and not anywhere near as durable as engraving. Save your money for REAL engravings.
I have answered this question a couple times on reddit, so I hope you dont mind if I just copy paste what I wrote there:
The process used to create these cards is called laser engraving. The cards are made of a coated metal (anodized aluminum), and they're actually incredible durable. Throw these things in box of rusty nails and they'll do just fine. Before committing to this process, we did a decent amount of scratch testing, and they stood the test. Maybe a video on their durability would be good for our video series! Am I saying these cards will withstand everything? No, that would be a silly claim to make, but they can with stand a hell of a lot. Now, if you're looking for a way to store your bitcoins so they'll survive the effects of a nuclear explosion, I may suggest searching for another method!
As for saving your money for "real" engravings, such as diamond engraving that leaves an indent, you'll have to save a decent amount of money, and the resulting product wont be that great. We tried many methods before choosing this one. Diamond engraving, for example, took roughly an hour per card, as the QR codes are so precise and cover a large area. If that the product you're looking for, it'd cost consumers around $80/card, and the resulting product is not really that much more durable, and the QR codes tend to have a tough time scanning.