However, I *have* heard that you don’t want to funnel ALL your money into these kinds of after-tax investments. If you do, you’ll certainly be guaranteeing that your income tax rate is lower at retirement as you’ll have no (or very little) taxable income!
I have seen suggested that one could invest in both regular IRA *and* Roth IRA. Then, you use the regular IRA up until the point where the taxes get a little high. Then fund the rest of your spending from accounts where you have already paid the tax.
As usual regarding investment strategies, I don’t think it makes sense to go 100% one way or the other.