Ok so I tried to test the max res at 24 fps.
I put it in 1280p @ 60 fps ALL-I. Loaded raw movie to res. 1920 @ 2.35 aspect, and dialed fps to 23.9. Zoomed to X5 (which I think is only X3 in reality from what Ive read).
Recorded movie, and it went biserk. The frame rate altered between 23.9 & 60 fps (canon default) and the picture was very unstable flashing purples/static/slow mo/pixelation etc.
The interesting part was I was able to shoot at a 1920x818, in agreement with the 2.35 aspect I had set!!! So there is some hope, if we can get the fps & pic stable.
Upon retest it looks like the 5X zoom dies / freezes within a second, even before one hits record. If you put it in 1280p @ 60 fps IPB, ML expects it to be shoot and select 1920 raw, ML reports it should shoot continuous which is a bug as well.