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Just tried a BMD rebreather for the first  time. Todd Ives (he trains people 
on the BMD) dove as my safety diver (babysitter). We did the north double 
ledge off of Palm Beach at 90 feet. Hardly a technical depth, but it was my 
first dive on one and I found this more palatable than pool time. 

Observations:
Its comfortable to wear (like a BC that fits well), not heavy compared to 
tech rigs. It felt fairly streamlined in the water, and I had no trouble 
keeping up with a normal spearfishing paced diver  with a single tank. 
I swam right up to a big Hog Snapper an a Black Grouper, and the quietness 
of the unit would have put me in a great position (if only Todd had agreed 
to let me use my gun on this checkout dive).  

Inhalation and exhalation at the surface was an effort. Once we hit 30 feet 
and deeper, this sensation was negligable. The air you breath is warm 
(because of an exothemic reaction taking place in the scrubbing process) and 
this is a strange sensation, but not a bad one. Bouyancy was easy to 
perfect, but the unit forces you to swim parallell to the bottom---heads up 
swimming, like when you want to flare up to see something, is hampered somehow.

The bailout mechanisms which Todd showed me on the boat were not intuitive. 
On this 90 foot dive I could have used the bailout system if I'd had a 
problem, but at 290 I would have been less comfortable. I think tech diving 
a rig like this would require us to relearn diving reflexes on the BMD for a 
few months  between 60 and 160, to really be as instinctually proficient as 
we are on a typical trimix or deep air setup.
This is not to say you could not dive this five or six times at 100 feet and 
then go deep, its just that you'd be thinking your way through the dive, and 
this brain power might be better applied to whats going on around you (in 
the same manner it would on the trimix or deep air equipment we  are used to). 

Also, if I was to buy this unit I'd use a Nemesis Nitrox instead of the 
computer the BMD comes with. It only computes a 32% mix, and this is bogus 
for a unit this expensive. With the Nemisis plugged into the high pressure 
port of the Odin (inside the BMD case) you'd have programibility from 21% to 
50% Nitrox in mix one, and 21 to 99% in mix two. For tech diving 
applications this would be mandatory for the whole concept to be practical.

Dan
Dan Volker
407-683-3592

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