I would suspect that a wet sub with rebreather gear would be a pretty nice
system. You get the flexibility of the wet sub, without the nitrogen
problems or time restraints of scuba.
Later,
Jon
--------------------------------------------------------------
   Jon Hylands      Jon@huv.com      http://www.huv.com/jon
  Project: Micro Seeker (Micro Autonomous Underwater Vehicle)
           http://www.huv.com