Raymond, I usually take at least one trip up to the BWCA for winter camping. I also like to do a couple trips a year in the winter months into the San Juans or Sangre de Cristo Range in CO. Last year I climbed Ellingwood and Blanca in January.
The warmest parka I own right now is the Feathered Friends Frontpoint. It's a VERY nice well made parka, but the fit on me has never been optimal.
I have at the house right now a Montbell Permafrost and a RAB Neutrino.. and will keep one of them. I also ordered a Neutrino Plus becuase I found it on sale and will consider keeping that one too.
I'm impressed with both the Permafrost and the Neutrino. Even though the Permafrost is baffled, I'm leaning towards the Neutrino.
Slimmer fit than Neutrino
Warmer, more loft
Better hood, more insulation surprisingly than Neutrino, wire brim rocks
Like the length better
Not quite as much loft, sewn through
They are both made VERY well! Comparable quality and materials, no difference there. The Permafrost in Med is almost too restrictive a cut for me, if I though I preferred that over the Neutrino I think I'd try a Large. The collar area is different on them, I don't know if I like the Montbell 'separate' collar or not. I like that it's fleece lined but I donn't think it'd be noticablily warmer. I like how high up my face the Neutrino can zip!
So, I will wait until Monday when I get the Neutrino Plus and that may be a better comparison to the Perafrost, although maybe even another small step up in warmth. I know I'm going ot be tempted to keep both RAB parkas!