Cain has said 9-9-9 is a transitional phase to implementation of the Fair Tax.
Fair Tax eliminates the IRS...bad idea huh?
Fair Tax eliminates Congress handing out tax goodies for favored businesses...bad idea, huh?
Fair Tax eliminates corporate tax, encouraging business to invest in the USA....bad idea, huh?
Fair Tax eliminates inheritance tax, payroll tax, capital gains tax, etc....bad idea huh?
There are books available to read up on Fair Tax, I suggest you read them.