said by emak:
Comodo free firewall is actually a great piece of software. Just don't install the extra crap like geekbuddy.
I use the same free programs you do Avast and Comodo, and I haven't found any problems with Comodo slowing down my system or anything. It just isn't as descriptive as my great old Sygate firewall. I could trace source IP traffic in my old firewall, but haven't found a way to do that with free Comodo. I'm just too cheap to pay for more.
If I was going to use a suite though, I'd use Charter's before I'd ever use Norton or McAfee.