Vincent vK wrote a review of Mammut Barryvox Opto 3000 Beacon on February 13, 2006
This beacon is really the best you can get today. It is small, reliable, accurate, robust and simple to use in emergency situation. My life was saved by one Barryvox 19 years ago (and a skilled user!). I can only strongly recommend them to anyone who is going to be exposed even to a LOW risk of avalanche! Use it every time you go out and enjoy your outings.