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As if it wasn't bad enough that they want me to use a random internet service to add a keyboard to a usb wifi receiver, they have the balls to put this for Firefox users. I clicked out of pure curiosity, as I'm not even remotely interested in involving a corporate internet service in getting my keyboard connected to my computer. This is the message you get now on Logi Options software if you have a Unifying Receiver: 
For the curious: https://logiwebconnect.com
EDIT: some people on the thread have brought up that the error message being displayed for Firefox users is due to the WebUSB API not being implemented by Firefox due to security concerns. This still does not justify having to use a web app to plug peripherals to a PC.
Quiet is a big factor. The blackwidow I have is the stealth edition, which is supposedly quieter than normal, but it's still pretty clacketty. I even bought a bunch of silicone o-rings to cushion each key, and it's STILL kinda loud.
I also feel like I have to push them way far down compared to a non-mechanical.
Scissor switches are like a little love tap and it fires, and are much quieter than any other type I've used. I'm just not super familiar with any peripheral company other than Razer (which has gone to shit hardware) and Logitech (which has gone to shit software),
From what I can tell Rapoo, Kensington & SATECHI all offer various scissor switch keyboards but they are all entry level, home or business keyboards which may not hold up to gaming & most don't have backlighting.
Another couple of switch you could look at are "Cherry MX ultra low profile tactile" (which look to be a combination of mechanical and scissor) and optical switches.