What crampons do you run? Thanks.In mid-August here in AK I'd expect to get snowed on and have low temps at or around freezing at or above 3500'. That time of year, the snow seems to come and go and daytime highs can swing pretty wildly from downright hot to pretty chilly. I have never needed nor wanted an insulated boot on an August sheep hunt. Walking in snow is less of an issue than prolonged exposure to sub-freezing temps. Even "uninsulated" boots do have insulating properties and synthetics, in my opinion, are warmer than most uninsulated leather boots. They dry out more quickly as well.
We are each different with regard to cold tolerance, circulation, and preference as well. If you absolutely can't stand chilly toes even for short periods of time, take warmer boots. I do get cold toes when sitting for longer periods of time in my sheep boots of choice, but then again I usually don't wind up sitting for long periods of time while sheep hunting.
For me late season goat hunts (Oct-Nov) are typically going to involve extensive travel in snow, crampon use, and temps at or well below freezing. I use La Sportiva Nepal Extremes down to about 15F, and then switch to La Sportiva Spanktiks for temps colder than that. As you might imagine, these boots get progressively heavier and more cumbersome as additional insulation is needed. I prefer to use the lightest boot that I can reasonably get away with based on conditions, and I usually err on the side of running a little colder as compared to sweating a bunch.