When was the last time you asked a human for driving directions? One day, the same could be true for financial directions.

Though many already turn to so-called robo advisers for advice about where to put their money to reach their desired financial destinations, MarketWatch wanted to see if these directions are any good. So we asked four prominent robo advisers and four of the traditional, flesh-and-blood variety to construct portfolios for a hypothetical 35-year-old investor with $40,000 to invest.