The Backcountry Big Mountain Ski.
This was my ski of choice for big mountain powder. With a touring binding it's heavy but exactly what you need to tour in the deep stuff. I had the opportunity to use this ski in BC last winter and skied everything from pillow lines to steep couloirs. I also took it up on Mount Washington in the spring conditions and it performed very well plowing over the mixed snowpack. If you are looking for a versatile powder ski, this or the Ranger 108 are excellent options.