Picked up a Subal housing for my D200 from Backscatter on Sat and immediately went out and gave it a trial over the weekend:
http://www.baue.org/images/galleries/album45
All of the images were shot with the Nikon 16mm f2.8 fisheye and the Subal glass dome port.
As background I've shot a lot of video over the years and have many still photographer friends but this is my first underwater still system.
So far I am quite pleased with the housing and the camera. The shutter release, aperture dial and shutter dial are all right at your fingertips and easy to use. I do worry that the right strobe bulkhead is a bit close to the shutter release and I found my index finger rubbing along the lock nut. Hopefully I won't accidentally unscrew it underwater. On the other hand this doesn't seem much different from other Subal housings and I haven't heard of anybody having a problem with this. I think this will be less of a problem once I get the weight of the strobes sorted out as my hands will be in a different position if the rig isn't negative (see below).
Most of the other camera controls work pretty well although I would probably prefer to have control over the AF-ON button rather than the AE/AF-L button. What I want to do is use the AF-ON button to get the focus close and then zone focus before shooting. With the housing as-is I have to focus by half pressing the shutter and then either hold down the AF-L button while zone focussing or move the focus switch from S to M if I want to leave the focus at a particular point. Works but is slightly awkward compared to using AF-ON. The one set of controls I had trouble with are the buttons for the multi-controller. You have to press them til they are flush with the housing to operate them and even then they don't always seem to work as expected. I don't consider this to be a huge issue but it does make reviewing photos more difficult than it could be.
Regarding reviewing photos the LCD on the D200 is great and was able to accurately gauge exposure and focus underwater.
For strobes I went with the INON Z240s. The strobe functionality of these guys is great but they do have some ergonomic issues. For one they are very heavy in the water. I'm going to have to figure out how to rig some floats on the arms or something, or else spent a lot of time in the gym as any strobe position that didn't have the center of gravity right over the handles was very tiring. Also the controls on the back are difficult to use with cold, gloved hands. An ideal INON strobe would eliminate the useless (IMHO) aiming light and the various auto controls to make the back less cluttered so the dials could be bigger and easier to grip. That and a bouyancy chamber to make them neutral or even slightly positive would be perfect.
That's all for now, more later as I gain some time on it.
Clinton