[JKnight]

It's not only about company match, lets not forget that 401k's allow you to reduce your taxable income and have more substantial annual limits.

Of course we'd all like to know that we're going to make so much money off our investments in retirement that we'll pay the tax now and avoid it later, but I'm not confident enough to make that declaration. For me personally, I'll use the same principles of diversification and apply them to my before-tax and after-tax investments.