I never liked Avast if you ask my opinion,so I am NOT excited at all about it,in my opinion (Avast fans,please don't rust at me,remember 'opinions') :
It is a suck-ish anti-virus. I'll go better find something better for free like Comodo Internet Security free edition or Kaspersky IS or Eset Smart Security (currently using ESS)
When I installed the 7.00 IS version,it slowed my Win 7 down so much and made my browser look like crap. Also,it actually got corrupted on my junk-pc while I was testing it against 0-day Malware (The PC is currently not-bookable).
Sorry for it. Also,they are not my favorite,sir. Kaspersky/Comodo are one of the kick-butt antiviruses. Sorry again