Be vary careful ... WIN uninstalls security systems.

Microsoft Security Essentials isn't the worst-but it isn't the best either. There are better free antiviruses if you want to put the time into downloading and installing one.

You said:

Microsoft Security Essentials isn't the worst-but it isn't the best either. There are better free antiviruses if you want to put the time into downloading and installing one.

Again, you can't exactly trust those because certain vendors have been proven to be gaming the system. To me, what's important is how intrusive the AV is. How much does it slow down your system. And Defender has always been the least intrusive of any I've found, while still providing good protection.

I think what's more important is a test of common malware, not every malware on the planet, including stuff that doesn't exist in the wild.

Mystere said:

Again, you can't exactly trust those because certain vendors have been proven to be gaming the system. To me, what's important is how intrusive the AV is. How much does it slow down your system. And Defender has always been the least intrusive of any I've found, while still providing good protection.

I think what's more important is a test of common malware, not every malware on the planet, including stuff that doesn't exist in the wild.

(For the record, common malware was tested. They give you the details of the malware they tested in PDF)

If Defender had better detection rates and better heuristic detection, it would be fantastic. It's too simple in terms of protection. If someone managed to hack an important website, they wouldn't just add an exploit that would download something that has been out for 10 years. And usually "proactive" protection would block new and unknown malware. Unfortunately, it failed to block 50% of those viruses.