Recently there was a thing where VAC would erroneously flag AMD's antilag+ feature as cheating, and issue a ban.
AMD then quickly disabled the feature by default but now Valve also patched detection for it and is now, at least according to these patch notes, reversing the bans.
It's really great, has a lot of depth, unfortunately the skin gambling is the worst part. I don't encounter cheaters in my game anymore, and play only with squads of friends and it's definetly my favorite FPS, would recommend to anyone willing to learn a tactical fps