Yea, these retirement vehicles aren't really my specialty as I plan on retiring well before those tax free deduction ages. I also don't really consider myself an investor. I'm far more of a trader.
Traders pay taxes too, in fact far more of them than a buy and hold investor. If you're going to be trading it is FAR more important that you shelter your trading money in tax-protected vehicles than it is for me. Think of it as a tax-avoidance vehicle rather than a retirement vehicle. Every time you have a short term capital gain, you pay taxes on it at your regular tax rate (slightly lower LT capital gains rate if you hold it at least a year). If that money is sheltered in a Roth IRA, you pay no taxes on it, even if you trade 3 times a day for a year. You still pay transaction costs (bid:ask spread and commissions) but at least you don't pay taxes. Trading is tough because you have to make enough good calls to overcome the additional costs of switching in and out. The average trader underperforms the market due to costs, so you should definitely track your returns (expenses included) very carefully using something like Excel's XIRR function to make sure you're doing well enough to justify the effort.
Also, keep in mind you can still get to your retirement account money before age 59 1/2. All Roth contributions can be withdrawn at any time for any reason without penalty or tax. Roth earnings can be withdrawn after 5 years for a first house, medical expenses, or education expenses. You can start withdrawing traditional IRA, 401K, or Roth IRA money even before 59 1/2 so long as you pay attention to IRS rules that basically say you have to take out substantially equal payments every year. Here is a pretty good summary I googled up:
http://www.rolloveraid.com/401kwithdrawal.htm
General exceptions: The 10% penalty does not apply to distributions that are:
1- Made as part of a series of substantially equal periodic payments (made at least annually) for your life (or life expectancy) or the joint lives (or joint life expectancies) of you and your designated beneficiary (if from a qualified retirement plan, the payments must begin after separation from service).
2- Made because you are totally and permanently disabled, or
3- Made on or after the death of the plan participant or contract holder.
4- From a qualified retirement plan (other than an IRA) after your separation from service in or after the year you reached age 55
5- From a qualified retirement plan (other than an IRA) to an alternate payee under a qualified domestic relations order,
6- From a qualified retirement plan to the extent you have deductible medical expenses (medical expenses that exceed 7.5% of your adjusted gross income), whether or not you itemize your deductions for the year,
7- From an employer plan under a written election that provides a specific schedule for distribution of your entire interest if, as of March 1, 1986, you had separated from service and had begun receiving payments under the election
8- From an employee stock ownership plan for dividends on employer securities held by the plan, or
9- From a qualified retirement plan due to an IRS levy of the plan.