When comparing Smuxi vs Colloquy, the Slant community recommends Colloquy for most people. In the question“What are the best IRC clients for Mac?” Colloquy is ranked 3rd while Smuxi is ranked 10th.
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 Free and Open Source
Pro Nice Native Design
Colloquy was designed with the Mac OSX interface conventions in mind, so it's got a native look and feel.
Pro Works on macOS Mojave
Although not supported anymore, it's been confirmed to work on Mojave.
Pro Has pretty themes like iOS "bubbles"
Pro Plenty of advanced features
Colloquy has many of the features an advanced user would need, such as file transfer support, and even support for mIRC colors. It supports scripting via AppleScript.
Pro Supports SILC and ICB
Pro Mobile version
Colloquy also has an iPhone version for IRC on the go with many of the same features.
Con Poor script and plugin library
Smuxi's script and plugin library contains less than 10 entries.
Con No longer supported
The app will not work on the latest releases of OSX as it has not been updated since 2014.
Con No way to search chat logs within Colloquy
Chat logs are not viewable within the app. You must go to the directory and open the file with a text editor.