Thanks for the info! I guess I should have been a bit more specific about myself before posting. Personally, I have extensive on and some off-trail backpacking experience, as well as climbing and mountaineering experience. I posted in the Newbie forum because I'm new to the forum. I'm also a newbie when it comes to the Cascades: I have in fact been there, but only as a teenager and only on trails. I am certainly comfortable on steep snow and know how to self-arrest; I am also planning on bringing crampons as well as an ice ax. I will be going with my girlfriend, who has done plenty of day hiking (including winter in the White Mountains of New Hampshire) and some backpacking, but no major off-trail travel. She has certainly used crampons and an ice ax, but not really in a situation where self-arrest might be realistically required (i.e. only on steep, but forest-covered slopes). Prior to this trip, we are going to spend several days in the Purcell Mountains of southeastern British Columbia, where we will do several day trips out of a base camp. I am planning on doing some self-arrest and snow travel practice with her at some point doing this trip - especially if we have a bad weather day. So basically, I'm trying to figure out whether the route I want to do is a feasible option for a relative beginner (though in good shape) accompanied by a moderately experienced backpacker/mountaineer.
Thanks again!
Alexey