The Poseidon XStream Deep is a reg built for tech diving, with a depth rating of over 600 feet. I approached it, however, with skepticism. Years ago, I bought a Poseidon Odin regulator, billed much the same way, and was forever disappointed with both its design and performance. Its second stage breathed wet and contained a flow button that, if left in one position, would cause a permanent deflection to the diaphragm. While it performed decently in cold water, it was far from the best cold-water reg I had used. Finally, it free-flowed anytime tank pressure dropped below 400psi. My buddies would be swimming leisurely back to the beach on the surface while I'd be making a mad dash in, trying to get there before it drained the tank.

I'm happy to say that the XStream Deep seems a much better reg. Although I didn't exactly push its depth rating, it did breathe effortlessly at 110 feet and did so regardless of body position. The second stage also exhausts well out to the side and is smaller and superior to previous Poseidon second stages. I used it in water temps down to 43 degrees and again it worked fine in these conditions. There are also plenty of low- and high-pressure ports located around the first stage for multiple connections. Operationally, this seems like a great reg.

One note, though. The XStream comes standard with a DIN connector, so to use it with a standard valve you have to also order a yoke connector. The XStream retails for approximately $500 and I wouldn't hesitate to recommend it for diving in just about any type of New England conditions. Fore more information, go to www.poseidon.se

Jerry Shine