This is really cool, and helps with immersion and all, but...I can't imagine why, in a hectic multiplayer shooter, you'd ever not want your gun pointing where you're looking. It's not like you suffer any speed disadvantages to do that in a game. In real life, I can whip my head around to get visual on something faster than I can move my arms to point at it. But in a game this is not the case. The OR may give you a speed advantage for turning to look in a given direction...but why wouldn't you want your gun to just come along for the ride?

I can see the usefulness of this in something that's a bit slower paced, though. For example, in a game where the concept of covering fire is implemented well, it could be useful to keep your enemy suppressed while being able to look around yourself. And for single player games it would just be awesome...the day they release a capability mod for Bioshock Infinite is the day I buy an OR, regardless of cost.