These three solutions are the best from one point of view: they remove active threats from your system. The one which excels is the one which manages to keep the system intact during the clean-up process meaning that after a successful cleaning operating, after reset, your system will work at its best. It is known, based on tests and user reports, that Symantec solutions, although have a high detection rate, have big resource consumption, drastically slowing the performance of your computer. On the other side, McAfee is light in resources consumption but fails at removing threats.
AVG, among other solutions, took advantage of the mentioned defects and excelled by being fast and responsive to active threats. Of course it’s not the best (this remains to user’s opinion) but it’s the best between those two mentioned.