I wouldn't buy the paid version of either, not because I'm a cheapskate, but because I believe the extra paid features are basically misfeatures. I also do a single-file scan of any software I download from any place other than the Apple App Store. (I remove them so that I won't somehow accidentally open them or forward them). I've never found any active viruses but I often find viruses within my email, in attachments to spam mail Avast finds them, Malwarebytes does not. A complete scan, including external drives, with Avast takes about twelve hours or so. I run Malwarebytes much more often because the scan is much faster. I have both Malwarebytes and Avast, in both cases the free version.
