I'd say it depends on the student loan interest rate. I locked in my student loans at 6.5% when rates were going up in 07. Then, they kept sending me those nasty letters telling me my new rate was 2.4% (if I hadn't consolidated). That being said, I wouldn't pay off the debt unless you couldn't qualify for any loan, or the interest rate was up around 7% or higher. Look at it this way:
You have 50k. Your payments are 500/month, and your balance is 50k. So, you pay off the loan and personal expense sheet shows a 500/month gain.
Now, put that 50k into a property with an 8CAP, maybe a 10% Cash on cash. Your income will go up maybe $400/month. Not as good as paying off the loan. But look at the big picture: over the next 9 years, your tenants will have paid down your mortgage maybe 15k, you'll have paid off the student loans, and you'll have a property that is probably worth another 15% or more minimum because of inflation. So, if you can hang in there with your current budget, the money that you would have used to pay off student loans can double or triple by the time the loan is paid off.... and you'll still have an asset when it is. Rule of 72... If you're invested at 10%, you'll double your money in about 7 years.
Now, when I did consolidate, I also moved from a 10 year term to a 20, which lowered the payment. And yes, I don't follow my own advice, I've been paying a little extra every month, but I wouldn't have if it was less than 5 or 6%.
That being said, if I knew more about your student loan situation, I might change my advice. Keep me updated.