Your CBA loan will come down to 6.24% this month with the latest rate drop.

You will have to pay break costs on your fixed rate loan (which could be big) and depending on how long you have had these loans you may pay a deferred establishment fee.

Another large fee would be the paying of mortgage insurance again as your LVR is over 91%.

To save a few monthly fees and maybe a 0.1% discount it doesn't seem worth it to me.