I demoed all of those except the Kass and Attack Ban.
The Dh2.5 and Ban Magic should be grouped together because both are suited for big mountain freestyle riding. The Dh2.5 is not a 7 flex for sure. It is at least an 8.5 in my opinion. Beast of a board. It is also the most poppy board out of the bunch. The pop in the dh2.5 can catch you off guard. Stability isn't an issue with this board. Not my cup of tea.
The Ban Magic is one killer ride. It's definitely softer than the Dh2.5. I'd give it a 6 in flex. Very responsive edge to edge and it likes to lay down a fatty carve. Pop is abundant, but not moon high like the Dh2.5. Also, very light board. You'll especially notice the lightweight on the lift.
The Park Pickle is a decent park stick. I'm not sold on the Asym heelside though. However, I already put forward lean on my bindings so that might be why. This one is a hair softer than the Magic with okay pop.
Ah, the Proto. You read my review so you know how I feel about this one