FLTEKDIVER:
Poseidon reg's are " upstream reg's " , If im not mistaken the odin is also. I had a Poseidon Extreme, and sold it because of that for cave diving.
The Atmoic M-1 will breath just as good at 240' as the Poseidon 's, if not better . Poseidon make a good cold water reg , their known for that, as well as good reg's, but expensive to service as well.
hi fltekdiver
only the oden or xstream SECOND STAGE is upsteram, the cyclon is down stream
none of the first stages in any brand, make them up stream or down stream
all first stages are piston or diaphragm
balanced or unbalanced
if you sold you poseidon because of the second stage
why did you not just change it to the cyklon second stage?
as far as service it costs about the same price to service a reg no matter what kind you have.
i have been diving with poseidons for the last 10 years and had never needed any hard parts, if you take care of them
the xstream has 1/4 the parts that any other poseidon has
and operates at 125 psi. intermediate pressure instead of 140 psi.
and still out performs all the other regs that are set at 140 psi intermediate pressure
also the xstream no longer needs a cold water kit
if the xstream did not breath to your taste it was because it was not adjusted to your type of diving.
hope this helps