Well, that's nice indeed... it's just it looks like you tried all the worst antiviruses out there in a roll... there is no way you wouldn't be able to clean your system if you tried Kaspersky, BitDefender, NOD32 or few others. Another thing... 20 antiviruses installed on one system (I understood, not in the same time of course
), if not uninstalled properly, each one of them would leave a lot of leftovers behind... which of course is not that good, and it would decrease efficiency of any antivirus out there, even avast! itself.