I don't really mean it as a slam - it's just "The Truth".
http://adultwebmasterinfo.com/ucj/
Take a look at the list of some of the top sites using the script. There are some big names in there, and some big #'s. It's hard to find a site that runs x-3 now-a-days... at least the standard x-3 traffic trade script. I know they do custom work for people and it's top shelf stuff. I think Zilla runs his whole site (trades&galleries) thru an x-3 script but it is customized Big time. The off the shelf model just doesn't stack up.