I personally just dealt with this same issue. I am an investment advisor so I like to assume I have an above normal understanding with regards to the investment markets. So typically unless the interest rate is over 10% per year I wasn't all that interested but just recently I had a change in my personal life when I found out my wife was pregnant with twins. So actually (just today to be honest) I went ahead and paid off the rest of my car loan and my wife's college loans even though the interest rates were both around 4.5%. I personally just wanted to slim my budget down as much as possible before the babies were born.
I agree with Bichon, the personal side of things has to come into the calculation beyond just the numbers.
Goldberg Financial, LLC
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