My Happy Hacking Keyboard. I have three in front of me right now, and a Rama in HHKB layout in a bag that I swap out when I want to feel real fancy, but usually it's all about that good feeling of oneness with cup rubber. I still keep a bunch of my old vintage cherry boards with vintage black switches (smooth like buttah), and some Realforce Topre boards because they too feel great, but they rarely see any substantial desk time as it's all about the One True Layout.
As to my history, I bought an HHKB Pro 2 in 2015, which I really liked, and it quickly became my main keyboard with the exception that it wasn't wifi/bluetooth so I could only use it with devices I could physically plug it into. Then in 2016 I found out about the HHKB BT, and got one shipped over from Japan. And it was perfect. Bluetooth capable, more aesthetically pleasing lines, actual rubber anti-skid pads on the bottom of the board, and overall felt like a more solid product. I bought a few more HHKB boards, including a couple Type-S for office and home, one of which showed up DOA, and the company sent me out an entire new replacement without asking for the dead one in return. So I did what any nerd would do and disassembled my beloved HHKB-BT, replaced the sliders with the ones from the Type-S, lubed the rails, and while I was in there replaced the domes with 55gm realforce domes from one of my TKLs. It instantly became my favorite of the bunch, I carried it with me everywhere, and I finally felt like I had hit that fabled storybook land of "End Game".
Here I am three years later. I own a Rama M60-a, three Tokyo60, the original HHKB Pro 2, a pair of Pro 2 Type-S, that glorious HHKB BT, and now I've picked up a pair of the Hybrid Type-S, one in black, one in white. I've tried BKE domes of every weight, 3rd party keys, 3rd party silencing rings, but nothing is as nice as my silenced 55gm HHKB BT. It's a bit of an addiction, but I just love that good feeling of oneness with cup rubber.