Kann nur den HÅG Capisco empfehlen. Nicht zwangsweise online kaufen, sondern mal beim Büroausstatter um die Ecke fragen, habe da einen ok'en Deal für ein Auslaufmodell bekommen können (Farbe).
Yeah, I've ran Mull as well, but switched when it was no longer maintained. Also learned about its successor from the other comments in this thread, good stuff.
I never went anywhere where I would have needed some, so i can't really tell but reading in some other threads it should not be problematic to put them on snowboard boots as well.
Boa, haha :) My take on them is just get a pair of rather stiff boots (I ride Insanos) and you will be fine; I rather need to loosen them a bit when my feet get cold. Stll not fully over the fear though of them breaking in the backcountry, but so far they kept up (and with some spare laces in the backpack for peace of mind)