When compared to other emu's...
-It keeps all the classic game mechanics and focuses everything added in around them (more details in a bit).
-Keeps the same database formats as eAthena used.
-Is the most up-to-date on formula's and mechanics for all the skills for the 3rd jobs and newer jobs skills.
-Tends to have certain features first before other emu's have them (body styles and dressing room for example) I love to experiment.
-Is normally always stable since releases are done more slowly to give me time to check my code that its clean, efficient, and bug free (rarely do bugs happen).
In a nutshell its something many like to use to host a server for a pre-renewal game mechanic server that supports all the latest jobs and skills. Yes Herc does allow this too but things like Hercules and rAthena are more better used for renewal servers.