I also too have the same fondness for Antivir from back around the 07-08 era. I have used the newest versions off and on through the last two years and I have never been too impressed, The detection lacking next to Avast/AVG, a noticeable system impact, and certain bugs that keep coming back from time to time. But, at the same time i don't want to see them just be another Avast/Avg under the hood either.I still feel some residual disappointment that Avira doesn't at least fare better for system performance. It ranked 14 in the last AV-Comparatives performance test.
I had a fondness for Avira AntiVir many years back. Does anyone have some recent experience with it? Does the core product work any differently from the SDK?

