Junz
I would suggest you first decide what you want to do with the camera first then choose the camera that fits your needs. I bought HVX200 for the variable fps at 720P. No other camera at this price range can do it. Other issues (P2 storage etc) have already been discussed in wetpixel and other forums, so please do a search for the other threads. Nothing I show you is going to be different except perhaps that it's underwater. I tested settings for my workflow only, not for general stuff. I believe Alan Roberts of the BBC has already put out a white paper of his findings, much of which I concur with except his treatment of skin detail and detail settings. The HVX200 is a prosumer cam with pretensions for broadcast.
If you are not sure about the camera, rent one to see if it's the one for you. I believe there are a few people who are renting the housings and cameras out. Contact Gates about that. Relying on my or anyone else's test and results will only confuse you more.
If you are a video professional, then you have to test yourself to see if you like the results. The P2 workflow is different and requires more initial purchases including a card read/storage etc and a rework of your present workflow.
I'm sure you already have Pana's excellent DVD on the ins and outs of the camera and accessories. Just realize the sensor is 960x540 and the inherit pros and cons of pixel shifting (lack of detail vs bigger pixels etc) and go from there.
The settings I use for underwater I hope to list out later once I'm happy with them. And hopefully I'll be showing some captures from the next 2 mths.