Hi I may or may not decide to hike the cdt during the winter this year in the wyoming and montana states and I'm kind of stuck on a bag choice. From what I understand a -10 degree bag is appropriate for those kinds of conditions at least but my budget is about $500 tops which leaves me with a quality 0 degree bag at best or some heavy synthetics. Does anyone have any ideas for me? Perhaps shine some light on the actual expected temps in those states during the winter.