The best application for writing new & editing music that there is (well, besides its bigger sibling, the Harmony Assistant):
1. Highly intuitive & fine-tuned interface, suitable for use by all, ranging from beginners to professionals.
+ you can write notes in standard keys or go for tablature / drum grid editing mode or just insert the chords or.. all is fully up to you
+ every instrument's properties (the look / editing style / corresponding instrument setup etc..) can be set-up per your desire within seconds
+ general no-nonsense settings for every aspect of the application
2. A plethora of options available to modifications; the pre-selected defaults are very reasonable.
+ as mentioned earlier, global settings follow a no-nonsense approach, are super-easy to understand and be modified
+ templates (modifiable / expandable) are providing a quick 'let's do things' option right out of the box
3. Quite fine digital sound samples, that can be replaced by your own; if needed, you can create your own sound-set and save / export it for future use - or just import an existing one you like.
+ you don't like this or that sound and have a better one? import it; you can import / export / save any sound(-s) / soundset(-s) you create for future use
+ you have a song in mind, so you write it and then you play it - during the latter, you can modify instruments / their properties / production / etc.. giving you an excellent on-the-fly feedback
+ you don't want to go with digital sounds? switch to MIDI - either by default or per instrument - it's fully up to you
5. Printing output capabilities.
+ once you have your score finished, you can print it or export it in graphical format, readable by many other 'industry-standard' applications
Personally, I use it (mostly) to have DRUMS track available for my later live-instruments recording (using Zoom R16, a digital multi-track recording & mixing device). Starting with version 3.4.0, I imported real-life drum sounds, as well as a few guitar / bass / keyboard ones - and all work 100% even in the latest version. So the process is - I have an idea for a song, so I write it down (typically tablatures & drums grids), then play around with its finesses - and when I'm done, I just export the drums (I mute the rest) into a stereo WAVE file (which I then import to Zoom R16 as a drum track). While I work on the score (and listen to it) I actually learn it as well, so the recording then is super-easy. Also, if I want to change a beat here or there ex-post, I just modify the corresponding drums track(-s), re-export them and replace the original (e.g. in Cubase) - as long as the starting point is the same, it's 100% OK.
All in all, this is, sadly, a vastly underrated application, that everyone creating music (no DJs/MCs/let's loop disco/hip-hop/rap samples type of 'musicians' (!!!)) should give at least a try. It's definitely worth the price (30 EUR).
LbnL I tried RoseGarden and NoteEdit (and a few other apps I do not recall the names of) - and NONE CAME EVEN CLOSE - in terms of intuitive & user-friendly UI and variety of options and possibilities.