Avast/microsoft Security Essentials/anti-virus

Can someone please tell me if MSE is as good as Avast in catching viruses? While going through my list of installed programs on Revo Uninstaller, I noticed how much of a "space hog" Avast is: over 1 GB! No wonder it runs like molasses in January! I also use Malwarebytes anti-malware so I'm covered there. I haven't heard much about Windows Defender since I haven't USED it so I can't say whether that is worth using.

I checked out a few other anti-virus programs (went down the list and read the comments) and am considering a few to try and see which works the best. I've tried AVG, Avira, and Comodo in the past and wasn't that thrilled with any of those. Have never heard of Clam, except for chowder (yeah I know bad joke). 360 Total Security/Essentials and Panda (free version) look interesting. Thoughts/comments/recommendations?

 

What is your Operating System and any Service Pack? I assume it is Vista or 7 as MSE is not supported on Windows 8, 8.1 or 10 - Windows Defender does the job on those OSs.
If you are on Vista or 7, you definitely do not need both MSE and Avast, and given MSE is now old hat, Avast is more up to date as far as its engine is concerned.

 

I knew I forgot something! I'm using Windows 10 64-bit.

 

As Max said, MSE isn't available for Win 10, which uses Defender. Defender is a direct descendant of MSE and, if you understand the basics of keeping yourself safe it will meet your needs very adequately - no need for third party AVs at all. However if you like to use file sharing sites and the like possibly you may need something else.