Comments about The North Face The North Face Pyxis Sleeping Bag Long:
I've tested this on a warm (~50 degree) night. Too hot if zipped up, but unzipped was very comfortable. I will update after I use it in colder conditions.
Only complaint is that the stuff sack doesn't have compression bands (it is just a simple, small sack) and it does not seem very durable. You will probably want to invest in a compression sack.