I don't think getting your util down to 25-30% will make a big difference to your score.  It will be some, but probably not enough to make a big % change to your loan rate.  With only 5% down I suspect you will gain more benefit from increasing this amount.

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Starting Score: 2012-10-06 EX: SSN has not been allocated!
Current FAKO Score: 2013-02-08 CK 675
Goal Score: 760+