I am going to buy this bag from Nunatak for 4 season use in southwestern BC
http://www.nunatakusa.com/Sleeping_Bag_Arc_Alpinist_Sleeping_Bag.htm
You can read more info about the bag here http://www.nunatakusa.com/arc_faq.htm
I am going to get it with the Pertex Quantum shell (orange or green????). Should I get the 2ounce down overstuff option to be sure I get maximum loft and long term loft out of this sucker? Also should I have it made with a differentially cut foot box? I will ask Nunatak these questions too but would like your opinions.
I am thinking that this bag would be great for all seasons. I the summer use it as a quilt, spring and fall layer my additional clothing under it and in the winter I would layer it with a belay jacket and pants (down or synthetic) which I would be carrying anyways to deal with cold weather around camp.
On a bag like this how far do you think I could extend the temp rating? If you had it what would you where to bed with it in the winter.
For winter layering I am looking at these too.
http://www.nunatakusa.com/down_sweater_skaha_hoodie.html
http://www.nunatakusa.com/down_kobuk_knickers.htm
http://www.nunatakusa.com/Down_Booties_Teanaway_Slipper.htm
With a set up like this what do you think would be my temp limit?
Any help would be nice. Thanks in advance.

