Beginning with Windows 7, I used MSE (the precursor to the current Windows Defender) and Windows Firewall on my systems, with MBAM as a supplemental scanner just to ensure MSE (or me) didn't let something slip by. MBAM has never found anything.
Since Windows 8, I have used the new Windows Defender (WD) and WF and now use that combination on all my W10 systems. Plus I use MBAM Premium on my primary system and MBAM free on all my other computers.
What's important to remember is the user is ALWAYS the weakest link in security. If the user keeps the OS and the security software current, and if the user is not "click-happy" on unsolicited links, downloads and attachments, and if the user does not participate in other risky behavior like illegal filesharing via Torrents and P2P sites or visiting illegal pornography and gambling sites, and if the user uses strong passwords and does not write them down on a sticky-note "hidden" :r1: under the keyboard, then odds are infections and computer compromises will not be an issue. Being behind a decent router with NAT is a huge plus too - even on networks of just one computer.
