I don't know if anyone could give you statistics, since most of the CO deaths you read about are accidents, but there are a couple of cons to the charcoal method. (A) It isn't as easy a set-up as it sounds, unless you're an avid camper with a few hours on your hands. I actually stocked up on all the supplies at Menards before I realized I'd just end up burning my tent down or killing my apartment neighbors with wafting CO. (B) Brain damage if you fail. Then again, if it works, it's one of the more pleasant ways to go. It's really too bad you can't reliably ctb with car exhaust anymore. All that requires is a garden hose, an exhaust pipe, & some duct tape.