I'll go first.
*K9 - Fast and pretty strong - problem is that without a reporting feature I don't think it has full effect. There is a real need for having a sense of "Ayin Roeh" - not just for the really bad stuff but also for just keeping you from spending 15 hours a week on youtube.
*SafeEyes - Really robust, many choices including categories, time restrictions (both amount of hours and times of the day), report to a friend, add sites, remove sites, etc.
1) Seems to slow down browsing (dealable IMO - an extra second per page load is a level of mesiras nefesh I can handle)
2) Bug 1 - getting online - I have had times when logging in in Libraries/Internet cafes caused me issues - they have a feature to deal with it but IME it doesn't work well
3) Bug 2 - adding sites doesn't work well - adding a site to the list of acceptable sites (ie. overriding a category (example adding macys.com b/c it got banned for lingerie/swimsuits)) doesn't always work - not sure issue (may have to do with multiple domain names (like www2.macys.com) but I don't think so)
... bottom line - it has pretty much everything it needs except it doesn't work as advertised. They may have fixed some of the issues and I imagine many people consider it good but I travel a lot and use the internet heavily. I need a flawless filter.
Therefore I am looking for a new filter. If someone could recommend one I would appreciate it.