I tried the Comodo about 2 months ago in a 5 yr old XP laptop. It was my 1st experience with an after market firewall. I installed it, and within 1hr I had the laptop unusable. There were so many pop-ups that I didn't understand, and I got worried, so I clicked deny to svchost..............Apparently that was important!
So I uninstalled it, and my laptop worked again.
It's probably great for an experienced user, but for me (Joe average) it was way to much info, all the time.