I do some basic security research and malware analysis online, so I've had a fair amount of experience with just about every Anti Virus software out there. Your best bet for malware detection is ESET Nod 32. For malware detection, it can't be beat. It's heuristic scanning is A+ and their signatures are always updated before others. However, EST is a bit intrusive. My favorite Anti Virus that I use personally is Malwarebytes Pro. It's cheap, they have very good heuristics, and it's not overly invasive. Shout out to Comodo as well.
