I think most of them have good features and bugs. This one is better than most, IMO: http://www.phplinkdirectory.com -- version 3 is in the works which will I hope correct some of the bugs.
Wasn't there an issue with that script getting people's IPs blocked from making PR check calls to Google servers? Disclaimer: this is just a rumor I "think" I remember hearing.
You can see the bug reports and solutions at http://www.phplinkdirectory.com/forum/ . As for the PR issue, displaying PR is an optional feature. Reportedly, requests for PR updates were blocked by some servers or by Google if coming from certain servers. As far as I know, most people don't have that problem but if you do you can simply choose not to display PR. That's not a phpLD issue but a Google or server issue.
minstrel, i looked at the B.O.G forum in your sig...its the best looking forum i have seen. not that i am anyone to judge of course, but i just thought i would let you know.
I've used 2 different (free) versions of WSNLinks and some of the other directories out there. Won't even bother shopping around now, WSNLinks appears to be so far ahead of the pack.
any chance you have a spare template handy ? i would love to tweak it a bit and put it on my new forum..... (not seo related)
So far, from my limited experiemce, WSNlinks provides the best value in terms of flexibility. I have a paid version good for three sites, and am about to buy a second license. Moving sites between categories and supporting a true directory are very good. However from a design point of view it looks ugly, since it has so many options, the default template is very cluttered. It requires a lot more work to get something you like. Figure on hours and hours of work. But the end results could be very very good. There are so many options it might be a bit overwhelming. One nice thing is that you can add fields to the tables fairly easily. At this point I have written a lot of add on scripts that help me do what I want. The support is very good, the documentation fairly bad. phplinkdirectory was much easier and faster to install and get a reasonable looking directory. I think less then three hours. However, the maintenance functions suck. If I want to edit an existing link, there is no easy way to find it, you either have to scroll through all the links trying to find it, ot write SQL scripts, or hack it in PHPadmin. For a simple link exchange it's a fastrack way to get something. SiteSift I just started looking at. No idea yet. I haven't looked at anything that cost more than $50