After playing around with the Mixcraft 8 demo, I found that it seems to work well, but it has too much duplication with Sonar features for me to use it as a secondary tool.
The Performance Panel grid is similar to the Matrix View in Sonar, with the addition of live recording into the grid clips (something that I haven't tried yet, but some might find this useful). I like the position they have placed the grid into, next to the track view, so that the grid rows are horizontally aligned with the track view. This does remind me of Project5, and I wish Sonar would do this with the Matrix (or else release P5 v3).
In addition, Mixcraft can follow project pitch with markers that can set the tempo, key, and time signature at any point. So as with Sonar's Matrix cells, when you import loops or groove clips they can follow the project pitch and follow changes based on markers.
I was also playing around with a demo of Ableton Live 9 (I have an older version), and as far as I can tell, Ableton does not seem to be aware of project pitch or key. A search through the manual turned up nothing. It seems that you can transpose a sample, but that is a manual process. The emphasis here seems to be with tempo and pitch stretching to match the tempo.