It depends on your personal financial goals and tolerance of risk. It is best to consult a financial adviser who will take the time to discuss the advantages of both and how they relate to your personal situation. No two peoples situations are alike. Depending on how the 401k is set up you may possibly stand to receive greater gains than a basic Roth IRA but there may also be a greater chance of loss. There are also a variety of ways these can be set up, so it would depend on the details of the products being used.