Hi there,
I have purchased mortgage watchdog and used this product and can't speak highly enough of it.
Not only did I run our mortgage through the software, I ran our seasonal finance overdraft through this software and was horrified at the errors our banks had been making.
I know it can seem a little time consuming at first but really this programme is fantastic and also prints out a letter to your bank manager and can calulate interest on interest etc.
Everyone who uses a bank should have this software and use it. This programme paid for itself in one month on our seasonal finance facility. I have run other family members mortgages through and consistently found bank errors as well.
Hope this helps all the queries above.

Cheers
Jackie