Do you believe the Hansen and Isis will have a larger soundstage then the Marten?
Difficult to say, soundstage is a product of room, speaker placement and even the electronics. I'm one of those that's much more sensitive to tonal balance than imaging or sound stage, but if I had to rate these I would put ISIS on top for sound stage, pretty much matched by Hansen and then followed by Kharma and then Marten.
This last statement is sloppy logic :^), based on listening in various rooms at different times. Perhaps another member will have direct A+B with these, although I think that's a pretty tall order considering price and exclusivity of these lines.