In reply to needvert:
Okay so after a bit of reading it's not Cuben fibre but a new Event/Cuben laminate. Seems that it is pretty breathable. Cuben is not breathable, it's used to make sails. And the weight reduction is negated if you have to take a roll of spinaker tape in your sack as it will likely get holed unless you are using it as a running layer. Horrible cut on the jacket though and only available in Dyneema white/grey. I'll be passing for the time being and letting the beta testers get back to us.
D