You should go to this website and use the appropriate mortgage calculator to run through your scenarios. The payoff calculators probably are the first place to start to see how extra payments affect the total cost / time.
http://www.mtgprofessor.com/calculators.htm
There are other things that you mention which may be more important. If you run into a phase of your life that may make it hard to pay the mortgage, of course it would not be wise to set yourself up for a bigger payment. I certainly would play it safe. The only downside is that if you have the
option o to pay off faster later, will you do it? Many people do not have the discipline and have to force themselves to the higher payment with a shorter term.
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