I've used Sibelius for many, many years. It's a totally different thing, and very mechanical sounding in playback. It's good for auditioning scores. A friend of mine uses its counterpart, Finale, to write music for major television shows. Of course, it's eventually played by actual musicians.
I'm hoping to actually use Sib to write by hand with a touch device like Eve.
I should add that when a sampled piano and some drum tracks are played on Abelton, my USB-2 devices get overloaded. I'm hoping TB or FW solves that.
Apparently, this discussion needs to be moved.....