Down the rabbit hole we go. I've been looking for a satisfying quiet mechanical keyboard for a few years now and think I've struck gold.
I had a Vortex Race 3 with Cherry MX Silent Red switches (linear) as my first entry into custom mechanical keyboards being my first silent keyboard. It was silent but the silencing O rings caused the key presses to feel slightly squishy. I loved it and used it for a long time but eventually got tired of it and wanted to try something new.
After researching for weeks on end I settled for another keyboard to replace my Race 3. This one was a Leopold FC660C with Silenced Topre switches (tactile). Let me say that Topre switches were everything I ever wanted feeling wise accompanied with a satisfying thocc sound. However being tactile switches they sounded slightly louder than the linear ones I had before. So... I got interested to build the most silent yet tactile keyboard I could make and started researching for the quietest switches on the market. After feeling the smoothness of the Topre switches I knew I wanted tactile switches for my next quiet build.
Here's my build after actively researching for what feels forever. A black Tofu65 with lubed (Krytox GPL105) Zeal Zilent V2 switches, lubed (Krytox GPL105) Cherry screw in stabilizers, brass plate, case foam and a DZ65 RGB v2 hotswap PCB. This keyboard is as silent as a mechanical keyboard can get without losing tactility. They do feel slightly lighter than the Topre switches despite being 62g and the Topre ones being 45g. I guess the rubber dome of the Topre switches gives off a slightly different feeling. But these Zilent V2s are quiet. And I mean quiet... I can't even hear myself type when I have my headphones on.
I will probably use my Tofu65 as my daily driver from now on and use my Leopold FC660C as my office keyboard.