In reply to Alex Hallam: I'm currently running a pair of la sportiva lo5's in 178cm
http://coldthistle.blogspot.fr/2013/02/la-sportiva-lo5.html
http://www.sportiva.com/products/ski/skis/lo5
I really like them and they seem to be a good one ski quiver for ski touring/ mountaineering and the ocasional powder day.
As for bindings I have the plum guides which are very similar to dynafit binding. They are defo the best type of bindings for touring as you don't have to lift up any extra weight under your foot when skinning up. They also provide the best contact with the ski. Everyone uses them out here for touring and mountaineering. .
I personally don't use a helmet when I'm ski touring but there are a few routes I would use one on if I thought the danger of getting hit by a rock/ ice from above was high. The only other time I feel vulnerable is when skiing a busy piste!!! For me all the ski helmets avilible are to heavy and hot for spring days trying to move fast and most climbing helmets dont work that well with ski googles. Perhaps there is a niche there or maybe I've not been looking hard enough.