I use NIS 2013 as my main protection with the firewall set to MANUAL so I decide what gets net access and what don't. I use Malwarebytes 7 Pro to actively run along side NIS2013 with no issues. And as a final and serious last line of defense I use Hitman Pro 3.7 Bld 183 to scan once a week. It uploads suspicious files to Bitdefender, G Data, Ikarus, Dr. Web and Emsisoft and you can also reg with virustotal for free and get a personalized API Key for Virustotal to be added to the list too! Bewtween these 3 apps you have:
Your base AntiVirus and Firewall (NIS2013)
An excellent anti-malware that can run along with your AV or just do scans if you prefer (Malwarebytes 7 Pro)
The 'final word' on any threat that gets cross referenced with multiple apps in the cloud as well as the venerable VirusTotal. (Hitman 3.7 Pro)
Granted, none of the versions I use are the free/trial ones, but when used together they present a VERY good defence.