I'll chime in here. I used to own the complete (full) NI series collection. I sold it because I couldn't write the sort of music I wanted to write with it. That's not to say it's a bad collection. It's a capable enough tool *providing you write within it's capabilities.*
Obviously, I can't go into massive detail else I'd be here all night, but here are some random comments:
Strings:
The auto-divisi is great and is a thing of witchcraft. Not often mentioned is that you can mix and match the divisi sections, reducing the ensemble size for more intimate productions. The legato is OK on slow and medium passages, but falls apart on faster stuff. There's a "fast portamento" trick you can use to smooth out some of the transitions, as detailed in one of Corey's videos. It works OK. The library ships with a convo 'verb active. You'll need it to smooth the transitions out.
Percussion:
Highlight of the bunch. Massive amount of mixing options and great sounding room.
Solos for woods and brass:
Here is where things get a little strange. Most of the solo legato lines are sampled (as far as I can tell) at a single dynamic which is something akin to a mf. I found assigning the mod wheel to cutoff frequency (along with "dynamics") helped get some variation in the parts.
There are other strange choices too. For example, the solo flute legato has no vibrato. The non-legato version does, so you'll be key switching like a crazy person. Lots of other strange random choices.
Regarding the effects, swells etc. I think someone above mentioned that they're fixed in time. If I recall, in the "multi articulation" patches they are indeed fixed. But in the "breakout" separate patches, time stretch versions do exist. This is the same across both woods and brass. Perhaps someone with the library still installed can confirm. That said, I never used them in the "heat of battle" so YMMV etc
Fake legato:
Something that I found quite useful on the brass and woods. For most sounds, there's an artificial legato available. Given the right mix and composition, this can be surprisingly effective especially when a "true" legato version of the sound isn't available.
Random musings:
I think there are better (and more expensive) libraries. But. At the current discounted price, if you're a Komplete or Essentials owner, it's astounding value. If you want the NI orchestral stuff under the current upgrade deal, I'd go straight for the full fat version.
I can understand people's frustrations with the NI orchestral stuff. You'll need to fettle with it. It's not "out the box ready" like, for example, Albion ONE. But with a bit of care, some time spent setting it up to your liking, and providing you write to the libraries strengths, I think it's pretty good.
Except the celeste in the percussion library. That suuucks.
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