Hi all,
Would like to add some thoughts.
I believe Kaspersky has some valid points, especially where Windows 10 will remove incompatible A-V software and set itself as the default security option . Also thought the Win 10 window for notification on updating incompatible security software was limited.
I currently use Kaspersky Internet Security. I have compared Windows Defender against KIS and other third party security vendors at this
site and have found a properly configured KIS to offer superior protection.
AV-Test.org does not give Defender very good protection ratings. Win Defender is baseline.
I also use Malwarebytes Free version as a second opinion. A great program. I have also used ESET, Trend Micro, and Norton AV for many years. All very good choices. I have luckily not had any bad experiences since 1997 using any of these vendors. Reticent to rely on Defender based on the above site test comparisons and real time checks at the other site.
Win 10 is a pretty secure operating system. The smart screen filter works well.
Jaco