My Arctis Expeditions are sized down with an Intuition Liner in them. The fit is much better for climbing in technical terrain, however it doesn't give the liner much room to expand at altitude (a small issue when I was up high...I just made sure to lace my boots super loose.) The deal with the Koflach boots is that they use a more flexible plastic around the ankle, which is great for walking around, but become a liability when frontpointing for a long time. My old Invernos were solid for ice climbing - the boot was more supportive and I could rest on the shell. Ice climbing in the Koflachs is still fine, but not quite as good. I'd still rather use my Supermountains or Nepal Extremes if its not butt ass cold. At least that's this crappy climber's 2 cents.