You want a 100 different answers? Wait fora 100 different replies from 100 people say XXX is only one that didn't let a virus in, one time, at band camp,so it's the best. Subjective and all have there pro's/con's.
Google antivirus test or something like that. There is a company/website that tests all the software every few months and ranks them based on how they do against a wide range of malware/virus/spyware/etc and run the at the top. In 3 months when they test again, run that one at the top. lol.