Sieto wrote an answer about La Sportiva Spantik Mountaineering Boot - Men's on April 23, 2012
I used the Spantiks on Denali last year. 7 out of a group of 8 used them, actually. They are warm enough, although on summit day you'll probably want a pair over overboots. You'd need those for the Koflachs too, so no difference there.
If I'd have to choose again, I'd go with the Spaniks again.