A few months back my pulminary dr at a respected hospital told me it was worth a try, but not at his hospital because of cost. The issue was it is not covered for neuropathy. Wounds that won't heal (often seen in diabetics), spider bites, etc are covered. It would have cost about $60,000 at that hospital for me to get enough treatments to see if it worked. There went that idea!

(Btw, he was in no way trying to sell this.)
Then, last month, my gym had a health fair and there were representatives from a wellness center that had both a hyperbaric chamber and a "smile studio." Although affordable it was not really the way I wanted to go.
Yesterday my chiropractor and I spoke about this subject and I found out his wife had gone to a different hospital that is also well respected to use their HC. It was not covered by insurance but not outrageously expensive. The HC they have is used for multiple people at the same time so I guess that keeps the cost down? I put in a call to them yesterday to get details and am waiting for a call back.