Coil whine is not a fault, as the card still works just like advertised. Some manufacturers let you RMA the card for coil-whine though. It is just a thing that is a part of some cards.
Kailh switches are a very close copy of the MX switches internally. The only real difference is the QC, or lack of and the failure rate seems a tad bit higher.
I like this forum as well. I lurked it for a few days before making an account, and it was nice. The only other forum I use is the Tek Syndicate forum, which is laid out like shit, but houses good people as well.