Certainly for the mountaineering part of this trip the Koflach Arctis Expe ($350) would be a good choice. Theyre a warm, plastic mountaineering boot thats perfect in cold weather and technical ice/snow. Asolos AFS 8000s ($440) would work well, too.
As for the trekking portion, well, I dont know. Plastic boots have come a long way in recent years, but theyre still not the most comfortable thing to wear for long trail trips. Theyre heavy and rather stiff. But then again, you dont really want to have a pair of plastics in your pack to lug around.
So, you could buy a pair of plastics and do some hiking around New York in them to see how they feel. You might find youre OK with using them as a hiker. Alternatively, you could buy a pair of somewhat newer-age boots that use materials that offer more comfort than plastic but have insulation and vertical-ice capability. For example, you might like the La Sportiva Trango Extreme EVO Light ($400). Its an insulated, light, technical boot made with synthetic leather and other tech-y stuff to yield a boot that can handle trails, ice, rock, you name it.
Scarpas Summit GTX ($390) is another excellent all-arounder. Maybe even better on the trail than the Trangos, with leather uppers, a Gore-Tex liner, and insulation. They are probably what I would take, if you want to know. I dont think youll be doing anything super-technical. But you want a good mountaineering boot that is warm and can handle crampons well. The Summit would do the trick.
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