Sounds like you get similar condition to us Down Under. We don't always get great seasons here and have to contend with mostly crap conditions. Mind you I bought the Atomic B5 specifically for my trip to Alberta/British Columbia in 2005. But I had to take for a ride for the heck of it and ended up skiing on it more than I thought ie on days when I wasn't skiing Bumps.
These skis do have their limitation of real hard ice as they are not exactly designed like a race ski ie. I have a pair of 163cm Elan HCX Hyperflex ski, which is about 3 years old. They are built in the traditional laminate sort of fashion with lots of metal in them and thet are great on ice. But its 63mm waist doesn't lend itself to being an all mountain ski , athough some days I am lazy to change them over and ski them everywhere. They sink in slush, crud and therefore require heaps more effort. Be that as it may you still need sharp edges from any ski when it get icy.
Sorry to carry on about equipment, you can tell I am an equipment junkie.
The Atomic B5 in answering you question were very stable at speed, I think the initial feeling you get from them is that they ski quite damped, but once you camber the ski mid turn they really have alot of power. Scalce was right in saying you should try the M:11 too less powerful , softer and more forgiving if you are a lighter weight skier and like bumps tree etc.. I use a Elan M555 when skiing in tighter spots.