I'm using tracktion now. I'll switch to eXT..
- When it uses full resolution parameter automation (instead of midi cc style).
When you can 'transient slice' audio that sits on the timeline of the sequencer (ie. not only in the sampler)
When there's a quick way to non destructively reverse audio on the sequencer timeline (or a quick way to copy and reverse audio clips destructively, without leaving the sequencer window)
When theres a decent audio timestretching function available


