See here for a recent report on views of the IPAB.
Particularly interesting were comments of someone who has been there and done things in the setting of a very important and powerful governmental appointed post.
Bruce Vladecks, the former head of CMS under Bill Clinton, had this to say :
"In the short term, it might theoretically work," he said. But the history with other independent regulatory agencies, like the Interstate Commerce Commission and the Civil Aeronautics Board is that over time "the regulated industries tend to capture them; and they tend to do more to protect the regulated industries than they do to protect consumers."
Considering the legislative hurdles that Obamacare put in place for Congress to over ride the edicts of IPAB, capturing IPAB would be prize well worth capturing.