I enjoyed the recent TGO review of down jackets as I'm looking to get a new one very soon. I currently have a Rab Expedition down jacket which is overkill for me and weighs just over 1.5kg. I'm looking for a lightweight down jacket for winter backpacking and my homework has led me to the Rab Neutrino Endurance (650g @ £200 and the PHD Minimus (380g @ £151 with Drishell). My questions are:
1) Do you think the PHD would be warm enough in an emergency bivvy on an extremely cold winters night?
2) How much warmer than the PHD is the Rab?
3)When reviewing the American jackets like the Western Mountaineering one, did you take into account their different rating of fill power? Do they really have 800+ fill power or is it 700+ by UK standards?