A Kinesis Advantage2 (almost 500 dollar in the EU, but read on). I had a flare up of wrist pain again. Decided to invest in a good ergo keyboard. Started with a Kinesis Freestyle Edge RGB (pretty good), then Kyria, Ferris Sweep (meh), and then I did what I should have done in the first place: buy a Kinesis Advantage2. It immediately felt great and after some weeks my wrist pain was gone. Concave key wells are just fantastic!
Since then, I also got an Advantage360 Pro (> 500 in the EU) and replaced the controller of the Advantage2 with a KinT [1], so that I can program it with QMK. I can now keep similar configurations between the 2 and the 360 Pro (which uses ZMK).
You can try increasing the debounce time to paper over this issue. Requires using a replacement controller like https://github.com/kinx-project/kint/ of course :)
I replaced the controller[0] in mine and moved the f-keys to a separate QMK layer so I didn't have to use the tiny rubber keys anymore.
I recently replaced the controller on my advantage2 to support qmk[0]. Using multiple layers lets me avoid the tiny rubber f-keys and move the arrow keys to hjkl along with a few other tweaks.
I wish kinsis would make qmk support a default option. Custom layouts and layers are just too useful for me to give up.
My https://github.com/kinx-project/kint project is a replacement keyboard controller for the Kinesis Advantage keyboards, which allows you to use QMK :)