I also have the same setup and fortunately have never had a flood. Are more expensive housings less likely to flood? I have not seen a head to head comparison of housings flood potential. Maybe the insurance companies have enough aggregate data from flood victims to help us find the housing least likely to flood.
Dennis
No housing irrespective of manufacturer could have prevented my flood, it was the standard "Oh-my-God, I-have-to-be-ready-in-about-20-seconds-to-jump-in" , bang on with the housing back and a horribly twisted o-ring that let half of the Red Sea into my housing in seconds. Furthermore I handed my housing to my buddy, who already was in the water, and he never checked for bubbles, so the camera was unbelievably soaked when I got in. But, as I said, no housing manufacturer could have prevented that, and I probably never will do the same kind of megastupid stressed entry with a camera again. What worries me more is that one of the push pins on the back of my housing felt very weird on one of the dives on my last trip. When I came up, the pin was loose and could be pulled right through the back. It turned out that the circlips securing the pin broke, and the pin was kept in place by the water pressure. One of my friends with the same housing had exactly the same failure, but he was lucky to and did not experience a flood. That is a likely flood reason that no kind of personal care can prevent, which makes me really nervous at times. However, then again, I have no idea of the rate of circlips failures for more expensive housings.