you will be surprised the tax rate be higher when retired

這個壇子裏的都有幾個出租房，退休時貸款基本付清了。這麽多年投資下來盤子大了。退休時稅率更高是非常可能的。

Roth has other advantages (no RMD), you can frequent trade without pay tax. The example you give, the $20k outside 401k will pay as income tax if you trade frequently.

I prefer Roth 401k over 401k