I should have known at $5.70 there was a “but...”. And it turns out these were shipped from China. I received them some five weeks after my order, which I guess is actually pretty quick.
Mach 3 really has no equal and is normally priced accordingly. However I’ve found that the blades last some 3x longer than competing blades, which effectively reduces the price quite a bit. And how much is it worth to never get cut when shaving?
I heartily recommend if you can handle the long delivery time.