A little tip I was given to speed up the inflation of my Exped Down Mat in cold conditions.
The built in pump works but rather slowly when cold but the intake valve is about the right size for a brewers demijohn cork.
Drill a few holes, or get one with a hole already in it. Cut the corner of a strong bin liner. tape the cork into the hole and you then have a home made pump back and £30 still in your pocket that you didn't have to spend on the manufacturers version.
