I've got 'em all but I personally only like Norton for their ability to seek and destroy adware, and GoBack, and WinDoctor. TrendMicro http://www.trendmicro.com/en/home/us/enterprise.htm
has an online virus, spyware, and security scan that is just as good as if you buy it from them, and that software will find trojans and worms that Norton doesn't detect, but only finds a very minute %of the adware that Norton can get rid of. At least check out the free online scan, you don't have to register or sign up for anything, it's really simple. Whatever you do Good Luck.