A can of worms opened here sure, but it's alwise nice to know what others use.
Toontrack, i once bought EZdrums, then a sale deal on superior drums. Latter i really like, a recommended SDX is Metal machinery, even if you don't like head banger stuff.

I prefer Cubase Pro, especially for it's extensive midi and audio tools.

EZ keys is a handy quicky tool, buy you usually spend a lot of time fixing occasional notes.

Matt, any experience with Dorico or even Cubase notation?

I usually stick to BIAB for lead sheets, melody/chords. Might be not enough for Jazz and Classical arrangement works.