1. Can't update (or takes forever)
2. Takes alot of CPU
3. Can't run i background (the program need to be "started" in window mode)
3. Can't understand what to do with the scanned files that get err 13 or other errors (alot of files, and also ordinary systemfiles, they say no permission), and even if you just ignore them they come up on the next scan again
4. Even scans it's own program (that is good) but put the application in list does not get a good expression
5. No help what so ever what to do with files in lists
6. When you get a virus, trojan, or other, you don't get a list what to do to remove it. No cleaning. No link. You can email it to avast, but not with any questions. You can delete, carantene (most trojans, worms needs more than delete to remove it from your system). I thought cleaning was included.
7. I have parallell desctop (bootcamp) with an WinXP and installed professional edition of avast (antivirus for mac + pc). Okey it warns that a trojan starts when i use IE, but it does not get an message to clean it.

Okey i'm not a professional, but I can't recommend people to buy this. I have already bought it but it goes into the trash for the mac part.