Where did you get your numbers? It seems a little high.
The most exciting thing about flat tax is that it eliminates some non-productive work from our economy. Tax Preparation and Tax avoidance strategies are NOT productive at all. They don't add to our GDP. Those who work in this segment will have to shift to real productive work which should create a boom. Another thing about the flat tax, you no longer get penalized for risking capital. That alone would give a huge boost to our economy. Eliminating the IRS, tax code enforcement and court time should really cut down our government expenditures.
If this rumor is true, wait for people (way smarter than me) to analyze the pros and cons of the NST.
The last bill for NRST called for a 23% tax inclusive rate, which translate into a 30% sales tax the way sales tax is traditionally calculated. You spend $1, 23 cents goes to tax and 77 cents goes towards the purchase. 23 cents is approximately 30% of 77. If you buy an item for a $1, it will cost $1.30 under the NRST.