I’ve played around with each of these a pretty good bit. I run IPCop at home and at a customer site, and pfSense I’ve messed with off and on, and have been impressed by it’s performance and features.
Despite what the title of this post says, however, I don’t think that it’s really fair to compare the two head-to-head. This is because they are fundamentally different in their aims; IPCop is determined to be a good SOHO firewall, and nothing more; pfsense on the other hand, has a decidedly more corporate feel to it. In fact, in the pfsense support forums, people offer feature bounties, where someone will offer money to whomever can develop a certain feature and incorporate it into the image. Now that is progress.
My experience in the IPcop forums has been less than stellar. I once posed a question regarding the ability to use IPcop as a transparent firewall, and was told that there would be no point in doing that with IPcop, since that isn’t what it was designed to do, and that I should try pfsense instead. Another user requested the same thing, and got the same answer. Still another user posed a question about when the 1.5 was coming out, since there were some new features coming out with it, as well as a new kernel. He was shortly ‘accused’ of being a Windows user, called a troll, and the thread locked. I read back over the posts to see if I had missed something inflammatory that he might have said to merit this, but couldn’t find anything unreasonable. That’s fanboyism for you.
I really like IPcop, and think that the core developers and the folks who have volunteered their time to create such cool addons for it have done a terrific job supporting it, but for the corporate user, pfsense seems like the better option.