I get a Personal Liberty Alerts newsletter every day and this is what they had to say about Cain’s 9-9-9:

The article says that while Cain’s claim that he will throw out the current tax plan may be true, his ability to replace it with 9-9-9 would take a long time, and the result would be only temporary. The research indicates such because 9-9-9 is the second of three parts involved in the Cain tax goal. The first step would cut individual and corporate tax rates to a top 25 percent rate, and the last step is actually the replacement of any current tax structure — even 9-9-9 — with a national sales tax or Fair Tax.

http://www.personalliberty.com/news/...rrid=387054256