I agree with nawhite.
Here's one scenario: Some 'stachers have relatively high working incomes, save a bunch of it so they can be FI and RE, after which they will practice simple living with relatively low post-retirement income. If this scenario is what you anticipate, then a traditional IRA has the advantage that you can do tax-deferred savings while your income is high, and then pay taxes in retirement when you withdraw at a lower tax rate. In contrast, under the same scenario with a Roth IRA you front-load paying taxes at a higher tax rate, and avoid lower post-retirement taxes.
As nawhite points out, there are other factors, such as different treatment of early withdrawals and uncertainty regarding future tax rates.