Finally downloaded the WZT Windows 8.1 Pro RTM. Install later and maybe keep using if no "big" problem happen... So, any antivirus suggested for windows 8.1 because I have use the online banking.....
Norton 360 Beta. I've been using on my preview build in VM and has been working great. And if Comcast is your ISP, you can get Norton 360 for free. I'm sure there version will be updated to the latest version as soon as it's released.
I'm using Webroot Secure Anywhere. In Windows 8 Pro, a friend is using it at 8.1 preview and we both find it great for a 700kb intsall-and-forget solution lightwight Antivirus.!! Not sure about Windows 8.1 RTM but I guess it won't be a problem for such a small program