desprateseagull said:balance what you may 'earn' interest wise on any savings, against the reducd capital on a loan if you dont need that cash.
a good mate has one, and says its good long term if you can afford to 'overpay' each month - the loan is shortened as you are paying interest for less time, on an amount that is reducing quicker that normal.
it makes a big difference to overall cost of the mortgage.