First of all, good on Google for developing a Bluetooth firmware the hardware they are otherwise bricking.

I have one of these Stadia controllers and recently tried to play Cup Head (a notoriously hard 2d shooter) with it. I found the Bluetooth latency to make this unplayable. I would estimate it to be 2x or 3x the latency of a PS3 or PS4 controller. Anyone want to pontificate on whether that's a hardware limitation or a software implementation issue? (I was playing via Steam on Linux and tried all 3 controllers.)