Since you are a fair tax supporter, I'll appeal to you to be fair.
I've looked at both ideas very closely. Both have their advantages and disadvantages. Neither is perfect, Although a consumption tax looks better from an ideological standpoint it brings with it a number of practical problems that I have never seen anyone adequately deal with, no the least is the double taxation on savings. Similarly the flat tax has its own problems; mainly it is still a tax on incomes, and as such could be open to tinkering over decades.
The truth is I would be happy with either as an alternative to what we have now. What I DON'T want is BOTH.
And here is where I ask you to be fair; there is no way you can fairly call Governor Perry's plan "tinkering with the tax code". That is so far from the truth it does not help the argument along. But sure, no legislation can bind a future Congress - only a Constitutional Amendment can do that - so your critique of the flat tax proposal can be wielded just as easily at the "Fair Tax": A future Congress could add rules, restrictions, exclusions and so on, and could even add reinstate a tax on incomes.
Now, that's a development that neither of us want.
So, push your favorite plan, no problem, but please do so in a way that adds to the debate.