Thanks, I'm versed on switches
there's a lot more to switches than the standard blues, blacks, browns and reds

the PCB is where you don't have to make the choice, as i said. there's no reason to use the outdated a.87 PCB that comes with a KMAC 2 kit, when you can get a KMAC-compatible NerDv2 PCB from GON. KMACs should be quite cheaper than a decked out GON, they're pretty old and i think their luxury status has fallen down a notch since a couple years ago
there are also a couple of upcoming korean kustom groupbuys. if i were you i'll hold off getting either a GON or KMAC at the moment. buying a high end product without doing proper research beforehand is very liable to give you buyer's remorse. but if you're committed to spending now, nobody here will stop you
edit: oh you're buying secondhand. in that case, choose based on aesthetics, layout and switches. price should be the last priority imo