I have the Q5 Pro, and it’s definitely thocky (and a beast of a slab of aluminum after having a few layered acrylic cases).
The Max is probably a bit less thocky with the extra foam (it has 3 more foam layers than the Pro).
I haven’t used the Shift V2, but for me the extra column of keys and the full ten key, was more important than the aesthetics and adjust-ability of the Shift case.