Temperatures in the desert in the winter are usually relatively mild, but it has the ability to get pretty chilly on a cloudless evening with nothing to hold in the heat.  A 3-season bag with a temperature rating somewhere between 15-30 degrees is more than adequate to keep one warm throughout the winter season.  The desert is a dry place which make it ideal for down, where there is little chance of wetting out a bag if properly equipped.

The Sierra Designs Arrow Rock 30 is my first experience with the “flex” concept that has begun to appear with several lines of Sierra Designs bags as well as some of it’s competitors.  My first reaction is to be impressed.  I am a side sleeper, and tend to toss and turn throughout the night.  Traditional bags have a tendency to bunch up and twist around me, forcing me to wake up several times throughout the night, and free myself from the mess.  The elastic baffles of the Arrow Rock 30 help a kinetic sleeper, such as myself, toss and turn, while still keeping the insulation close to my body where it is most efficient.

The Arrow Rock 30 is stuffed with 600 fill weight down, and weighs in at 2lbs 5 oz for the regular length, and 2lbs 9oz for the long.  I am 6ft tall, and am testing the long, which leaves me with a bit of room in the foot where I can really burrow down in the bag.  The Arrow Rock 30 stuffs down to a reasonable 7in by 17in in its provided stuff sack, and with a compression cask,  I could see it stuffing down even smaller.  The 40D polyester lining is soft, with the 30D exterior being just slightly beefier.  There is a small stash pocket near the head area,  and a voluminous hood  that looks to allow me to cinch it down with a small pillow inside.  I am curious about the attached sleeping pad locks, and their effectiveness, as I have never had this feature on a previous sleeping bag.

The best part is that Campsaver.com has the Sierra Designs Arrow Rock 30 for as low as $109.98