Why is it all or nothing. If you are looking to lower your rate and maintain some level of securrity why not heloc out part and keep the othe wher it is at. For instance if you have 400K outstanding at 7% by going with %25 heloced you now have a weighted average interst rate of 6.31. If interest rate did start to move adversely you would only have to worry about a small amount. In the interim You could continue to pay down the 7% loan with the saved interest reducing the amount of years that you are paying on the loan.
It is not an all or nothing scenario and it seems like ther is definitity to lower your borrowing cost with a modest amount of added risk.
