For couteaux the two possiblities in this thread seem to be the best bet
http://pistehors.com/news/forums/viewthread/231/
It is an interesting choice. Doug Coombs was a big advocate for wider skis mounted with the Dynafit binding and given that the Coomba is named in his honour it seems kind of fitting. Coombs philosophy was that wider was better for most skiers as it gives a better platform for turning and in difficult snow. You then save weight by choosing a light binding. A Dynafit ST will save you 1.5kg over a Marker Duke. Ok it is not exactly the same programme as the Duke or Baron but it is a proven backcountry binding.
The Coomba is 135mm/102mm/121mm which is pretty wide so there are the usual drawbacks:-
i. Making tracks will be hard work, even if there is an existing track most ski tourers are on around 80mm skis these days so you will be left widening the trail. Snowboarders on snowshoes will love you though.
ii. They will be fairly heavy - did you find out the weight?
iii. Traverses on hard snow will put quite a bit of torque on your leg and binding. You will probably find using crampons easier in these circumstances. Maybe it is not even worth bothering with ski crampons for such a ski? I know a number of experienced skiers who prefer to go from skis straight to boots and crampons on safety grounds. The rub is where the snow surface is a hard crust that breaks under your boot but not your ski.
iv. You need to make sure your climbing skins will fit and stay on with such a large shovel. BD wire hoops are probably the best bet.
My big worry with bending the brake would be that it would no longer function reliably. You should also be aware that if you lose you ski on a steep slope the brakes will do little to stop them. That is where the Dynafit comes into its own as it is simple to block the binding - you don’t want your ski to pop off if you hit some crust on the edge of a steep couloir. For steep skiers a broken ankle is preferable to a 300 meter ride down the mountain.
There is a move, even amongst serious ski mountaineers, towards fatter skis. You can ski them short which gives better maneuverability in the trees and in tight chutes.
I’ve not skied the Coomba, or indeed anything that wide. I would be interested what people think of the sidecut for steep skiing? K2 give the turn radius as 22M. It is similar to the Snoop Daddy which a lot of people like for Fatcountry skiing.
