No, I don't think paying off a 6% loan is the best place to invest your money. If you invested in a fund that matched the S&P over the past 25 years (approximately 10% return), you should have over $125,000 rather than $48,500. There are some tax implications that I am not considering though: home loan interest is deductible; capital gains that pass through mutual funds are taxable making ETF funds more attractive but you can get index funds in both I would think; or you could have put the money in an IRA with no tax implications (for a while). The best part about investing is that you have liquidity (money to take a vacation or help you through a period of unemployment) rather than having to sell your house or taking out a home equity loan to access that money.

You can use the Future Value function in Excel to figure out the future value of a stream of payments. Here's the formula I used to answer the question =FV(10%/12,295,100,0,0) or 10% interest divided by the number of months in a year, the number of months in 24 years, 7 months, the dollar payment amount, the value of your investment now (0), and the payment is made at the end of the month (Excel places this value at 0)

There are some pay-off-your-mortgage-fast products out there now and I am planning on covering all the nuances to those programs in future articles and then discuss why paying off early isn't necessarily a great idea.