Offer your thoughts or opinion on the input financial query or topic using your financial background.

Student loan payments and opportunity costs
Ponder this. Suppose that a reputable company or government were to come out and say hey, we are going to issue some 10 year bonds at 6.4%. Anyone interested in buying some? Assume that the company or government is financially solid and there is zero chance that they will go bankrupt. Think those bonds would sell? Would you be interested in buying such a bond? Well, I would wager that these bonds would sell like hotcakes, despite the fact that the long term stock market return beats it by a half percent. Heck, vanguard's junk bond fund is hot right now. It only yields 4.9% and those are junk bonds, not rock solid companies (see vanguard high yield corporate bond fund) Every time you make an extra principal payment on your student loan, you are effectively purchasing a investment with a rock solid, guaranteed 6.4% return for 10 years (or whatever time you have left on the loan if make no extra payments). On top of that, paying off a loan early builds your credit reputation, improves your monthly cash flow once the loan is paid, may increase your purchasing power for a house or car, and if nothing else, it frees you from being a slave to that debt payment every month.  Edit Improved wording based on Ross's comment