It's pretty good now a days. And the PITA to setup is worth it, because unlike many other IMs, it allows you to setup your incomming and outgoing ports for any of the protcols. This means I can actually send and receive files from behind a NAT without having to forward specific ports that are "fixed".
Not to mention the fact that the plugins are cool. The history ones needs some work, I might be half tempted to make my own, it's kinda crappy right now.