Who will audit my sales?
Your friendly folks at the Fair Tax Enforcement Division, who formally worked enforcing the IRS code, -- who else?
So then what have we gained? You are replacing one hated bureaucracy for another.
A much smaller bureacracy, for only one 'gain'. Others have been mentioned here.
-- Obviously you haven't understood the rationality behind the Fair Tax, even if you read it.
Do you have a vested interest in the income tax system?
Apparently I am paying less in income taxes than I would under a NST.