Jean M.wrote a review of Outdoor Research Helium II Jacket - Women's on March 4, 2018
Familiarity: I've used it several times
Fit: True to size
This jacket is a neat colour (bright turquoise), but felt a bit more plastic than I thought it would and was a bit more sweaty than I had anticipated.
However having said that, it was very useful when hiking Bryce (in -14C), Zion, Arches, Grand Canyon and Yosemite National parks as I kept it in my back pack (it’s extremely light), and used as a wind break when we stopped for a break in the cold wind while winter snow hiking. I knew if I was really cold I had it in my pack and would feel warmer straight away. Although not for this purpose I also used to sit on in the snow. I haven’t tried in rain. It runs pretty true to size (I am 128 lbs and 5’6” and with the M I can fit a few layers underneath and still move. It would be even better if it were longer so that while wearing you could sit on it.