I'm new to using quilts, and I found that if I pulled the down overquilt (JRB No Sniveller with a Rocky Mountain Sniveller as the underquilt... feathery bliss!) over my head, it was warm and toasty and the quilt material was kept away from my face. In a short period of time, I did not find any problems with condensation or stuffiness (it is presently 16 degrees), and my nose appreciated the reprieve from the cold.

Are there problems or concerns associated with breathing for an extended period of time in such an enclosed space? I would hate to wake up dead one day...