I purchased the K8 Pro roughly 1 month ago and have since spent that time using it to create an informative review. I've used mechanical keyboards for around a decade now but to no great depth really, mostly the overpriced gaming brands as well as Das - always with brown switches.
The K8 Pro is a game changer. It's well priced and delivers far higher quality, extensibility and customization than any other that I've used. The frame is nice and heavy, well built and very durable. The keys are smooth, with each keypress being absorbed nicely. There is no wobble on the edges of the spacebar, like many other mechanical keyboards seem to suffer from. Bluetooth supports 3 devies which is perfect as I work from home with a company laptop, so it's easy to switch betwen my PC and work laptop.
My only criticism is in the switches on the side, particularly the power switch. Currently the options are, in order, BLUETOOTH - OFF - CABLE. A more appropriate configuration would have been OFF - BLUETOOTH - CABLE. It is far too easy to get stuck in dance, if you will, with the power switch when trying to turn off the keyboard. That is, if you're in BLUETOOTH mode and wish to switch it off, you may very well push too far and land in CABLE mode. Then, if you try to go from CABLE to OFF, you might end up in BLUETOOTH mode again. The grip on the switch isn't great but I'll not knock a star off for that as it's not a conscious decision that Keychron have made. Obviously, limitations with the switch will be the issue here, since the top and bottom positions will close the circuit while the middle position (OFF) opens it, it's an ON-OFF-ON switch. I don't know if there are any switches with OFF-ON-ON positions.
Nonetheless, aside from that minor niggle, this is a really powerful, customizable and well built keyboard. I will stick with Keychron for the foreseeable future.