Here is a race video while I am wearing the arm restraints (you can see the big Sparco logo on my forearm). You may have to click through and watch it full screen to see all of the detail.
As you can see, I am working the wheel pretty hard in a few spots and shifting with no interference from the arm restraints. Like I said, I forgot they were there.
https://www.youtube.com/watch?v=ZWKv3WtUkOY