SocalDiver:
I've been shooting u/w stills for about 10 years and video for over 3 now.
From my experience, it's easier and faster to become skilled at shooting u/w video vs stills. The reason is that you get immediate feedback by being able to review your work right after the dive. You'll definitely get more enjoyment and satisfaction out of it, and in the long run, it's cheaper. Why? Because if you don't like the results, you just rewind and use the DV tape over. When you shoot stills on film, you're out the cost of film and processing.
I've made over 150 dives with my first Sony Hi-8XR u/w video system. My video housing and lights are from Ikelite. SP mode tape length is 2 hours and battery life is 4 hours. This system has served me well and my results are great overall. I've been able to sell content filmed with this setup and it's paid for itself. The Hi-8 content transcodes well to DV using a digital 8 deck and I'm able to edit all my content on the PC using Premiere 6.0.
This year, I started to work for a team producing a television show about Florida diving. The project owns a couple of Sony VX-1000s and Amphibico housings (expensive.) As highly touted as the VX-1000 is, I think it's over rated underwater. The battery life is short and fixed to one size. Also, 3-CCD cameras are not very good with low-light conditions. You need big lights to get good results with this setup. The Amphibico housing is one of the best with the most advanced features. You just need to ask yourself "do I really need everything I'm paying for?"
If I was to buy a new system now, I would go with a Sony TRV-900 (for a 3-CCD) and a PC-110 (for a 1-CCD). Being a single CCD camera, the PC-110 is better for low light but won't have the extreme dynamic range of color of the 3-CCD camera. Both these cameras can support larger batteries giving 4 hours of record time. However, DV tapes limit you to 1 hour.
For housings, I really still believe that Ikelite makes great housings for the money you spend, and their service is top-notch w/ no hassles. Their mechanical controls work well at depths less than 150 ft. Your system should have external color correcting filters that can be removed underwater if the camera and housing don't support white-balance control while underwater. DO NOT get a system where you screw the filter onto the camera and then put it in the housing. The filter needs to be removable and replaceable during the dive for flexibility with lighting conditions.
Whatever you get, use the hell out of it. Items in this technology seem to get obsolete pretty quick.
Hope this helps somewhat.
Good luck,
Brian D.
Sarasota FL
SubsurfaceMedia.com