I currently use a Coronaire Maxi for water. I have known for years that an oxygen fed machine will give you much stronger ozonated water than an air-fed machine can hope to, even if a good air dryer is used and the air dryer is maintained properly. It just makes sense that 100% oxygen (or nearly 100%) will make cleaner, stronger ozone than 20% oxygen and whole lot of other gases we find in room air. When used with oxygen, a machine can also be used for many other protocols like the auricular insufflation you mentioned. Air-fed water ozonators are OK to get started with, but IMHO merely a small step along the ozone learning curve.