I use IE (have for the last 10 years with no problems.) - but much of the security resides in the bank's software. BAC uses two layers. First, you must login to see a graphic key you can change regularly. Second, you apply a password to that graphic key. The program is also sensitive to what computer you are using. When ever I use a different one, like my laptop, it goes into security questions. When you log out, you should completely close your browser as well. USAA bank asks you to do that.