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I disagree - it would benefit you!!!!
now $270,000 x 4.25% x 30 = P/I $1327 x 300 (25 years left) = $398100
compare to $270000 x 3.5% x 15 = P/I $1928.29 x 180 = $347,092
Savings $51000 by restructuring to a 15 year mortgage.
I would be wise to talk to your current lender about doing an in-house 15 year refinance, thing way there is little to no closing costs.
It would be unwise refinancing to another lender because you would incur title and legals charges, origination and junk fees, eating away at your equity.
First find out what you can qualify for talking with another mortgage banks. It is important not to commit to any thing.
This will give you information you can use to negotiate a better deal with your existing bank. Get them talking about the lowest rate, then go one step further ask if you could buy the interest rate lower.... (that's what I would do in your case)
Good Luck......
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