I had used Avast free versions for several years before purchasing back in 2014. I've run 1-2 licenses since then and was steadily renewing. In the last couple of years the quality of this product has declined. I have Windows 8 & Windows 10 systems. Plus paid for a subscription on my son's laptop.
1. The GUI is slow and clunky.
2. Faced app malfunctions leaving my system unprotected. Had to use phone support. That was not a good experience at all. I had observed similar issues on forums. Did not seem to have been handled well.
3. In-app ads in the paid version for other Avast products. GUI being so difficult to use, I was never able to figure out if it was possible to disable them. They were obtrusive and worsened my experience.
4. By far the worst and why I finally unsubscribed is that it was too slow. On both my systems, especially after waking from sleep, they disk thrashed for 10-15 minutes. I suppose there's some scan that needs to run. Whatever -- I was often just powering off instead of waiting through it. Easy to repro. Browse, watch some videos with Chrome, read the news, check your email. E.g., just use your computer for a long time without turning it off. The browsers are memory hogs, which isn't Avast's fault. But it needs to co-exist efficiently.
I'm using BitDefender Total Security now. GUI is noticeably smoother vs Avast's and the laptop is much more responsive overall. No in-app ads so far. They do seem to have similar upgrade options, main point is there's no ad getting in my way.
I was a big fan of Avast and hope they listen.
