BenMMusTech
I've started dabbling in orchestral stuff and in particularly virtual orchestration...I think we need to stop worrying about "real" orchestral musicians personally, the virtual stuff can do the job these days. I'm not sure about the sounds, I use notion which is suppose to have the superior sample set over Sibelius. I also do a lot of audio engineering stuff to improve the sounds too, you'd be amazed at how a little transient shaper can make things pop and zing. I tend to take all the individual orchestral sounds and give them their own track either via rewire or bouncing. This allows me to use better verbs and in most cases two verbs for a realness you can't get with the orchestral propriety verb. Then slap tape sim an console sim. I'm only just beginning too, there is arguments for double tracking as well.
Ben
Notation capabilities are the more important than the sound, so Sibelius is the definite choice over Notion. Also, what you're hearing isn't Sibelius' sounds. It's Note Performer. It does a vastly superior job of "interpreting" the mechanical notation (it prefers "mecahnico" input, which is the stiffest MIDI imaginable), into something that sounds roughly like how humans would play it. In that regard, Note Performer stands alone. I do have several of the high-end libraries (Cinebrass, LASS, VSL) which sound infinitely superior, but the labor to play those parts and navigating all the 'niggles' of those libraries isn't worth it unless it's to be used as a final product.