The big thing to remember about temp ratings is that they are pretty optimistic for most people, while if you have a bag rated to 30 degrees and it gets to 30 degrees you will not freeze to death but you may not be comfortable either. If you are in an area that it rarely gets below 30, I would recommend that you buy a bag rated to 10 degrees, 0 degrees would be even better. They cost little more and can add to your comfort considerably. Now as far as the Wiggys bags goes, I have one of their light weight bags and like it, but they are expensive. I went with the Wiggys because they compress to a very small package and you can leave them compressed and they still fluff to retain their insulation qualities. Mine is only rated to 30 degrees but that is fine because I use it during the spring, summer and fall. I have probably close to 100 nights in mine now and I only have one complaint in that the way the ziipper is made, it can get uncomfortable if you twist around and wind up laying on it but that is a minor complaint for a infrequent event.