<< I guess it depends on what you're trying to do. If all you want or need is to run a firewall and keep some bad things out (or in, depending) then ZA or tiny are just fine. I use ZA Pro (I like to support good software) and am happy with it. BI Defender gives you boatloads more data, just in case you want to reach back through to whomever is trying to hack you and rip his RJ-45s out. 😉 >>
In the same note, it can easily give you more false positives. I got tired of explaining to some of my friends what the heck was going on so I told them to get ZA. False positives are almost as bad as real attacks...