Microsoft Security Essentials Offline Update

does anyone use this software for protecting computer from virus, etc?
for me, this is the best antivirus for windows 7. Because it's from microsoft.
to update manually, you can download this package and then just double click the file. it will update your MSE virus definitions.

* Update virus definition for MSE 32-bit:
http://download.microsoft.com/download/DefinitionUpdates/mpam-fe.exe
or
http://go.microsoft.com/fwlink/?LinkID=87342
* Update virus definition for MSE 64-bit:
http://download.microsoft.com/download/DefinitionUpdates/mpam-fex64.exe
or
http://go.microsoft.com/fwlink/?LinkID=87341


another best antivirus for windows 7