“…rebreathers, I have learned some important lessons (Comper & Remley, 1996; Pyle, 1996d).
After my first 10 hours on a rebreather, I was a real expert.
Another 40 hours of dive time later, I considered myself a novice.
When I had completed about 100 hours of rebreather diving, I realized I was only just a beginner.
Now that I have spend more than 200 hours diving with a closed-circuit system, it is clear that I am still a rebreather weenie.” Keep this in mind when speaking to rebreather divers. Many ccr divers and instructors speak as “experts”. The most terrifying are those who actually believe it of themselves. There are few rebreather divers today who have more than 5 years on the machines. When I began diving ccr in 1999 few to none were diving them, even in the tech community.If we consider what Richard Pyle says as probable, then even when one first receives instructor ship they are “beginners”.(100 hours required)Find an instructor who has paid their dues, spent time on the machines and not just in a pool or teaching courses. The 100 hour requirement to begin an instructor course does not mandate type of dive or depth. I’ve heard of instructor candidates getting in a 20 ft body of water and breathe to get their 100 hours.Following is a list of some assets a great instructor would have:

More than 8 years diving CCR:

gives the instructor a solid base of ccr dive experience
7 or more years teaching CCR: instructor has experience and established protocols for communicating vital information to students
teaches more than one brand of unit: has a thorough understanding of various unit design and  operations
test dives new units coming to market: trusted by those “in the know” in the community to safely dive and assess new equipmentThere are only a handful that fill this outline. Choose wisely.