ARMA 3 seems to have Speed Sensitivity to allow for more "realistic" transition in turning when using a mouse and keyboard. The problem is when using a racing wheel, even if you have deadzone's turned off, it tries to "auto-correct" your steering based of your acceleration/speed at the time.

The problem with this is the controls then feel "laggy" or "unresponsive" compared to the real time adjustments of the driver using the wheel, especially if their wheel is 900 degrees. (Which in turn creates unexpected behavior).

There should be at least an option to turn this off, or at least a slider. While it can add to "realism" and lead to better control for keyboards, it causes a lot of problems when using it with controllers. (Coincidentally, Gran Turismo had this same problem until GT5)