In your opinion, is Halion 5 better than KONTAKT 5. Just trying to make up my mind about getting Komplete 9. How doesn't perform in Cubase compared to Halion 5.
Very difficult to answer ...
Kontakt integration into Cubase leaves a lot to be desired. No expression map support, clunky drag/drop support etc...
On the other hand Kontakt 3rd party library support is unrivaled. It has a very deep scripting engine, and a lot of editing functions that are amazing ... if you can stand to use that interface.
Halion is in many ways cumbersome and convoluted to get used to, but as a sound creation tool I think it is unmatched. As a sample library player ... eh maybe not. Plus Halion is not a great tool for creating 3rd party libraries. The Borgz seem to want to control that. So, it doesn't look like it will ever get in the game for that purpose with Kontakt.
I have both and find myself using H5 in nearly every project. But, I like to do custom sounds, not library playback. Plus I use VSL for orchestra. And the combination of HSO and VSL removes another reason to load up Kontakt.
So basically, if 3rd party library support is important to you, I'd go Kontakt hands down. Other than that, it is a tough call.