I meant relatively silent i.e as silent as possible. As mentioned, I was using Cosmic Byte gk 28 vanth with red switches. I was OK with it.
I couldn't repair the one I had. So not sure about repairability.
If there is one which I can repair even in the case of PCB or controller gets faulty then I would be ready to invest in it. Otherwise, makes no sense.
I wish we had repair manuals for our keyboards.