This PBT keycap set is really something. I've immediately mounted them on my Cooler Master QuickFire XT keyboard. They feel sturdy and they have a little damper sound than the original ABS ones. The grease will not stay on these keycaps, that is for sure. Thanks to the seller for correctly guiding me to buy a proper product for my keyboard because I wasn't sure what to order exactly.
Eh. It's a bit expensive, but side-engraved doubleshot kepcaps are hard to come by. I guess it works well enough. The molding is a bit weird, though, and the legends feel a bit fuzzy on the edges.