Actually, it’s Alwil that’s on top of everything.
I just read a post about two new varients of a virus which was discovered late yesterday while the audio part of the Avst! update notified me that another update had just been made. I’d call that service with a smile and I was the one smiling.

The settings in Avast! really depend a lot on the user. The more stingent the settings are, the more time consuming they become. (To a certain extent.)
The default settings are pretty much middle of the road. On my system, it’s set to scan every thing. I really don’t have any problems with those settings and feel more secure that way.
Try the link in my signature. It may be of some help to you.