Steam Hardware

It is very effective for me, I can play multiplayer fps games against mouse and keyboard players fine and honestly I enjoy it more than mouse and keyboard, probably because I grew up playing xbox/consoles (not that I find it difficult to use a mouse and keyboard, just not as fun) but also because it just feels like I am aiming so snap shots and such are wayyyy more satisfying to me than if I just moved a mouse to click on them.

In practice it isn't necessarily easy to tell I am using gyro except for when I do brief quick reaction shots just relying on gyro for aim, the rest of the time I don't ever think about using the gyro consciously, I just use the joysticks for rough aim and let my brain figure the rest out with the gyro. Recoil in FPS games is also way more fun to control with gyro, it is a more direct control relationship rather than dragging a mouse down a mousepad, at least for me.

I don't move the Steam Deck much though, it isn't like I am getting a work out whipping the Steam Deck around, the gyro is really just there to lock in broad joystick movements to be accurate and on target consistently thus avoiding the small aim adjustment problem that joystick deadzones create. Also once I got used to it, my brain automatically cancels unintended gyro movements with joystick movements and thus I don't have to hold the Steam Deck totally still in order not to have my aim utterly thrown off from a normal amount of arm shake/movement.