I have been using a DIY PLUQ and thermarest camprest deluxe pad in both my ENO Dbl and new to me WBBB here in the mild Pacific Northwest and have found it to be just a bit cool between 30* & 40*. I decided to order myself a late Christmas/early B-day present in the form of a 40* Phoenix and am now somewhat biting my nails over the decision, maybe should have gone 20*... My thought was that this is primarily a non-winter sport for, me read not below freezing, and most likely a motorcycle camping kind of setup, maybe some summer hiking. My thought was that this lighter version would have the most seasonal use and not be as likely to "overheat" in the summer/fall when I expect to use it the most. If I wanted to go cooler I could add clothing and or pads. Just looking for validation of the thought process while i might still be able to modify my order I places last night.