In my humble opinion, the best "antivirus" is none of the above. All of them are resource-wasting and ultimately ineffective.
First off, I'm going to say that I have not had a single virus since I was a kid and viruses were first becoming a problem. I'm by no means a computer genius, but I do know more than the average person. I know certain file types that can be "infected" with a virus, and I know file types that could not possibly harm you, even if it had virus code in it. Simply scanning every file that comes by is pointless to me. On top of that, it is an extreme waste of resources.
With all that being said, my first line of "defense" is
VirusTotal by
hash check. That means if I have an .exe or .dll or anything that I was personally suspicious of, I would use winMd5Sum to get the md5 hash of the file then check it up with the constantly updating database of VirusTotal. If the file has not been scanned recently (which rarely happens), it will give you no results and you would need to upload it. After uploading the file, it will test it against 40 different antivirus programs.
40 is a lot better than 1. It also will give you a good idea of when some files are just false positives, and when some files are 100% surefire viruses (for example, 3/40 could be a false positive, but 39/40 is a definite virus). Not only that, it gives you the message reported by each antivirus. This can be helpful as "Suspicious File" (which can just be a false positive) does not really tell much compared to "Trojan-Proxy.Win32.Small.ez".
Even when a file has a low danger level (say, 5/40 programs report it as "Suspicious"), I still have a method that does not pertain to antiviruses that will help protect my computer. I will run the file in a
sandbox to make sure none of my actual files are harmed.
This method is not recommended to all, as some people simply do not know enough about computers (or it gets too complicated) to keep a computer safe with just VirusTotal and Sandboxie. For those that do, though, I do not see why they still have an ancient piece of technology like antivirus software installed on their computer. I'd much rather take a minute to upload a single file and check it, then scan every bit of incoming data on my computer. In fact, I can't stand the thought of there being an additional process booting on startup (except for my Firewall, as that is crucial).
Anyhow, sorry for the essay, but that's what I do and I have many virus-free computers that have been running since the 90s to prove it to be an effective method.
