I just bought one of these as a bag liner/summer bag. Just thought I'd post the link to a review that I read at Backpack Gear Test which seems to reflect my impressions almost exactly (but I like the color). I only tried it once since I got it a week ago, in my back yard, and it kept me reasonably warm (I slept in it for three hours on a stone patio on an old Thermarest 3/4 with a bluefoam foot pad). It was a little tight in the shoulders and hips, but very efficient because of the close fit. It got down to 30 degrees with a wind of 10-20 mph.
http://www.backpackgeartest.org/revi...rol%20Crooker/