The New York Times says KF94s, made in South Korea, are “one of the best options” for masks. I assumed that a couple of months ago, when I bought a few on a hunch that the quality control in that country was more trustworthy than that in China for KN95s.
Pro tip: If there’s one near you, go to a Korean supermarket like H Mart to find them. They’re often pretty well stocked with KF94s.