The question is: Do you intend to submerge the camera?
If you do intend to submerge the camera, I wouldn't feel comfortable with this system (Unfortunately, proper underwater housings with reliability at depth cost thousands of dollars). That's also to say nothing of the control difficulties introduced by using a rubber cover with your hands on the outside.
If you don't intend to submerge the camera, then Kata covers already fill this role and do so without interfering with control. I use a Kata E-702 to shoot paintball and storms. I trust it for everything short of wading into water.