I have used ZoneAlarm Pro firewall (7.0) for a few years and endured the bugs and hiccups but been fairly happy. Finally I've decided it's time for a change after seeing ZA slip down the rankings and also after discovering that ZA is repsonsible for constant disc activity on my XP machine. I've no idea why and i'm not going to spend days trying to find out but the fact that there is brief disc access every couple of seconds means the HDD is never idle and therefore never spins down, resulting in less than stellar battery life on the laptop. So I'm now looking at the top 2009 contenders (OA, Comodo, Outpost, PC Tools) and wondering which satisfys my broad criteria of a solid firewall with minimal bells and whistles, minimal CPU and memory useage, and a quiet HDD! It'll be protecting an XP laptop that travels with me a lot and uses a fair number of public access points. AV/AS software is Eset NOD32 3.0 with Spybot and Ad-aware. Some P2P use. I'm fairly tech savvy so don't mind helping configure the software and dealing with its learning process.