This is alot cheaper Don than the $400 Analox. I was thinking of getting one but no one seems to have them right now in the Toronto area (well at least at the 3 LDS I called).
What do you think of it really? No alarm until 50 ppm but I guess you just have to look to see if it's above 5, 10, etc. and make your decision to use the tank or not.
Perhaps the stores there are hesitant to stock the Analox unti because of your stricter compressor regulations locally? This site offers the Analox for $325 US
EII CO- Portable Carbon Monoxide Checker with free shipping in the US, somewhat higher to Canada.
The Pocket CO will work. If I really liked it, I would not also own the Analox - but you can certainly use it for safety, and easy enough for a couple of divers. Here are my cautions and how-tos from my experiences and mistakes...
1: It is susceptible to contamination and misreadings from humidity and a variety of urban fumes, so stick it in a ziplock before you leave the plane and keep it in one. (I do wear mine turned on while sleeping on planes since none have their own and I think it'd be nice for someone to know if an onboard problem happens.

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2: Use
slider, freezer grade gallon bags as they are easier to close, but take enough for a new one/day as they still tend to leak after handling.
3: Turn on the unit and crack the tank before sticking the bag to it less you learn how easy it is to blow one overboard if you hold the bag to the tank then open! That's how I learned. :silly:
4: When the bag is mostly full, close it, turn off the hissing tank, and start your stopwatch/SS timer. Wait 90 seconds or longer and read.
After your first trip, order the calibration kit in time to use it before your next. $39 plus shipping at
Order the Pocket CO - Carbon Monoxide Detector Re-cal for every trip or every 6 months, whichever is later. It's good for a year, then replace.