The major disadvantage with the task scheduler trick of using ashquick.exe is, it will scan every file of the hdd, partition, folder or file that you set it to scan; even those files not considered a potential threat, this can take a long time. It is possible to add certain folders to the exclusions list for say your media files, etc. This could leave you vulnerable if that folder got infected as it wouldn't be scanned by the on-demand scanner as you have excluded it.
The Pro version gives a lot more flexibility and the scan would follow the settings and exclusions, etc. of the regular scan.
With the different levels of protection (Web Shield, Internet Mail, P2P and Instant Messaging) and the fall back of the Standard Shield, I find the need for daily scheduled scans lessened. I prefer to do a manual scan with my regular weekly maintenance tasks.
