Very cool. A local friend said he didn't like the Petrel at all because with gloves on it would sometimes hit the side bump sensors that act as buttons. Also hitting the left button with the thing on your wrist and near you is an awkward user interface. There are some newer competitors out there but I like the looks of the units, figure used market deals might be pretty decent and the EXT interface for o2 cell monitoring is pretty straight forward in case I ever get around to getting CCR cert (or decide to hook it to an o2 unit I take to the quarry once in a while.)