I went cheap on my first "lightweight" bag, and honestly think I did pretty well. For $70, I picked up a 30 degree Slumberjack bag and am still using it today. Compared to the 6 pound behemoth I used to lug around, the 2.5 pound Slumberjack was a welcome addition to my gear list. However, the 30 degree rating is WAY off. I need to wear a fleece and warm socks for anything under 45 degrees.

I'm saving up for a Golite Ultra 20 right now.