If you could only upgrade one camera housing, what would you do

Ia have a 5d mark 2 and a 7d. I have a housing for the 5d mark 2 but nothing for the 7 d. If you were going to get a new housing would you get a nice housing for the 5d or the 7d. The current housing for the 5d is ikelit. So it would be 7d subal and 5d ikelite as a backup system, or 5d mark 2 in a subal. Primary focus is still photos, but really getting into video...

Well how practical do you want to be? Having the same housing brand for both cameras means interchangeable ports.

Personally, unless you want to shoot with high ISO over 1600 and full frame (where there are no real advantages except resolution and ISO performance), I'd house the 7D in a good housing. The resolution is near the 5D2 and the AF system is slightly faster and more accurate (and certainly more flexible with 19 pts vs 9!). I find the 7D sensor caters to more shadow noise than the 5D2.

I personally like a housing that has Q (info) and the joystick access. Almost everything that's needed is on that Q menu. That left me with 3 housing choices, Sea and Sea, Aquatica and Nauticam.

Of the 3, I'd pick the S&S because of the controls. The Nauticam I discounted because of the 3 clamp design (I only have 2 hands!), but the ability to have 2 fiber and 2 sync cord ports was nice. Aquatica was tempting because of the hydrophone accessory, but the sliding tray was problematic for me. It too has a fiber port.

The Sea & Sea has only extension rings and limited port options, but companies like Zen and Inon cover it well for accessories. The controls just felt right. It is also the most expensive of the 3 I believe. I ended not buying a 7D though.

The Subal is exquisitely made and the internal controls are gorgeous, but the joystick control gives control to a shooter that allows faster shooting. I never did try the Hugyfot so I can't say anything about that housing.

Now my comments shouldn't be seen as pejorative to the brands mentioned, it's just my preferences. Plenty of people are happy with these brands. The good news for you is the 7D and 5D2 market will have an influx of 2nd hand systems as people upgrade to the 5D3. I just sold my 5D2 housing. Good luck.