[nemetroid]

Lilypond is quite good for transcribing music. It's compact and quick to write, so you can get the job done quickly, and the layout engine is actually good out of the box.

However, I once tried a (small) composition project in Lilypond, and it really slowed to a crawl when I started to make major changes to what I'd already written. The ability to "refactor" is just so much easier in a visual editor like Musescore or Sibelius.

Perhaps for more experienced composers, with less of a need for complete redos, tools like these are better at "getting out of your way".