When comparing Smuxi vs IRSSI, the Slant community recommends IRSSI for most people. In the question“What are the best IRC clients for Windows?” IRSSI is ranked 9th while Smuxi is ranked 14th.
Ranked in these QuestionsQuestion Ranking
Pro Twitter integration
It's possible to check and interact with Twitter's timeline, replies and direct messages from the Smuxi client.
Smuxi offers an option to keep idling in a channel even when all front-end clients are closed. It's possible for a front-end client or multiple front-end clients to connect to a single server. This allows setting up an always on-line server that can be accessed from anywhere.
Pro Plugins and scripts can be written in any language
Pro Highly customizable interface
Pro Facebook chat, gTalk and Jabber integration
Smuxi has XMPP protocol support that allows integrating with Facebook chat, gTalk and Jabber.
Pro Theming support
Pro Caret mode
Caret mode allows navigating through messages (the output buffer) via keyboard.
Pro Perl Scripting
Allows the user to create and use perl scripts to perform actions.
Pro Persistent Connection
Pro Command line outputs can be sent to a channel or message
/exec -o figlet "Slant.co"
Allows the modification of IRSSI's look and feel.
Pro Free and open-source
Pro Has a plugin for encrypted communications
Con Poor script and plugin library
Smuxi's script and plugin library contains less than 10 entries.
Con Gives little direction upfront
Actually, Irssi.org has it's own GREAT documentation.
Con Cryptic configuration files
Con Can't do vertical splits
Untrue, there are perl scripts available to do split screens with
Con No GUI
Actually a plus, lower memory overhead