Some financial institutions register mortgages as a "Collateral Charge", which means the mortgage is registered for more than the actual loan amount. Other financial instituions may provide a choice, or register the actual mortgage loan amount.
Potential advantage...
A collateral charge may make it easier to access additional funds or a line of credit with your mortgage in the future.
Potential disadvantage...
To change financial institutions at renewal time, you may incurr legal fees again. However, some other lenders may help cover certain fees to switch to them.
Here's the important part...
A collateral charge may be the right fit, or perhaps it's not for you. The important thing is that your mortgage professional has that conversation with you and provides you with options. This is an example why interest rate is not the only important factor to a mortgage.
As I always say, rate is important, but so are the other policies in your mortgage, so be sure to work with a professional that you trust and will explain your mortgage policy to you so you'll have a mortgage that will meet your needs into the future.
As always, I'm here for you. Got a question? I'd love to answer it for you. Reach me at sarahnm@mortgagegroup.com