On a few occasions, including today, I heard a very experienced diver who uses a lot of Helium declare that he will never get into rebreathers because they are too dangerous. Regardless of what one thinks about rebreather safety, whether they are very dangerous, only a little dangerous, or not dangerous at all, I wonder how the situation is changing over time. Have rebreathers actually gotten safer over the past 10 years, and if so, in what aspects? Is more reliable hardware now being sold? Are better procedures being taught? Is good training easier to come by? What is the trend believed to be, and in what areas does one expect improvements (if any) in the near future? Or, are rebreathers just as dangerous (or not) as they were a decade ago? And, if you are one of the people who believe they will never get into rebreathers: what technological breakthrough, or other improvement, would need to happen for you to change your mind? (Disclaimer: I'm not getting into rebreathers just yet, just curious.) Thanks!