I know this could probably go in Software, but since it's a "security" subject, I'll stay in this board. I mean this post with NO disrespect for Zone Labs for I am, thus far, a happy camper with their current firewall, but rather a question of "features" of the Pro version compared to the free one. As I read the description chart, the Pro (paid) product has about three things that one doesn't get in the free version: Triple Defense Firewall, Anti-Spyware and Email Security. I'm not sure where Identity Theft fits in, so I'll ignore that topic for now.
It seems to me that these three topics are in the same arena as Symantec, McAfee, Trend Micro and others who market "package" products to do the many jobs that individual software products do as standalone applications. For example, I use the antivirus component of Trend Micro for all around virus/trojan protection, MailWasher to do "front end" analysis of my incoming emails and, like most of you, a series of malware programs like Spyware Blaster, AdAware, Spybot and others to protect me from those kinds of intrusions.
The three items I highlighted seem to me to deal with those same topics and therefore a bit of overkill on these topics. I was going to quote the descriptions from the Zone Labs chart but I'll leave it to you to read those at: Zone Labs Feature Comparison Chart.
I welcome your enlightening comments and tutorials.