I used to use ZA, however, it was sucking my resources dry. It took a whopping 6% on my Win98 box. I switched to Tiny and it uses no noticeable resources! I was tired of having to reboot just about everytime I went back online. Tine also allows me much more flexibility in setting permissions. I also noticed that ZA did not block all of the 'web bugs' that Tiny alerts me of. I was really surprised about that.
Tiny is great and I now recommend it and discourage ZA.