Hehe, the feature that enables that (feeding reading the PTY and feeding the VT parser off the main Emacs thread) only got merged today. But the rendering even before this was a lot faster than Vterm.
Otherwise, I think the main advantage over Vterm and other Emacs terminal emulators is that it handles modern fancy TUIs a lot better than Vterm. It's backed by libghostty-vt so supports all the new fangled escape codes. It has a bunch of tricks to force fallback glyphs to the terminal monospace grid to remove the flickering effect when the glyph cells change size during TUI animations, most notably in Claude Code. Btop and Yazi runs great too, if you're into that sort of thing.
Plus a bunch of other things!
Just to expand a bit on "bunch of other things". You can see a vterm vs eat feature comparison here: https://dakra.github.io/ghostel/#ghostel-vs-vterm
Besides the performance and what baokaola already mentioned some things that make Ghostel better than vterm especially when working with those cli agents are:
- proper handling of resizing windows
- progress reports (you get a spinner in the modeline when claude thinks)
- notifications (get an alert when your agent is done)
- drag and drop works
- hyperlinks. urls and files are clickable