Hey P,
I won't speak to personal usage, that would be silly since I am the manufacturer and you already read all the marketing text on our website, so I will skip that, too.
Let me just inform this thread that the reg is Poseidon...no surprises there. Poseidon does not make this particular combination of first and second stage (Xtreme first stage, Jetstream second stage) and it is a very nice combo.
As for performance, it is a higher performing reg that the 2500 in deep waters...this is an IDEAL reg for deep water..the dang thing practically breathes for you. Deep water wreck divers swear by them.
They are more expensive to service (they do not fall under our free service parts for life as long as the reg is serviced every 2 years/100 dives policy) and they must have their own hose (with the built in safety valve). Because this is an upstream valve, it does not fail "open" as you are accustomed to. Instead it blows off building pressure from a safety valve in the hose.
It's a phenomenal reg, my husband had been diving one for years prior to me joining Dive Rite. We now use them on our sidemount rigs due to the sidebreather characteristic makes it easy to use on the left riding tank.
Best,
Kathleen