I’m seeing about 4.5% now. We were at 5.75% for 5ish years (from 2003) and then went down to 5.125% a year ago. We’ve got enough time to pay that it’s worth considering refinancing if we can get 4.5 percent now (it’d save us 150ish a month) but it’s not dramatic enough to be a slam dunk. Last year’s refinance saved us nearly 350 a month.
In your case I’d consider it anyway, if you continued making your current payment or at least paid down the new loan over a 6-7 year amortization vs the planned 15 year payout (assuming you refinanced to a 15 year loan). It might be significant.