As of recent, Windows Security (aka Windows Defender) in the latest versions of Windows 10 seems to far surpass any of the other anti-viruses. In fact, many of the other anti-viruses these days are just performance hoggers and are, in my opinion, a downside just due to the amount they detect vs. how much performance they take and how much annoyance they cause. Windows Defender used to be next to useless, Microsoft overhauled it in Windows 10, especially in the most recent updates.