Windows Defender ruling Windows 8.1 preview

Microsoft released Windows 8.1 preview with the new Windows defender.There seems to be a compatibility  problems with Windows 8.1 preview and other antivirus products.Even though Symantec stated that their antivirus is fully compatible with Windows 8.1 but there is a problem with all the antivirus programs. So for now, users who use Windows 8.1 preview are stuck with Windows defender.