Mike Bromberg wrote a review of Outdoor Research Helium Hybrid Jacket - Men's on April 24, 2014
Familiarity: I've used it several times
Fit: True to size
More versatile and only very slightly heavier than the lightest windbreakers available, the helium hybrid is ideal as a light and fast wind/light precip shell. For ski mountaineering, alpine climbing or multipitch rock and even mountain biking, this piece is great when a little extra weather protection is needed, but a full on waterproof shell would be overkill.
I've used this extensively this spring (30 days or so) for ski mountaineering/backcountry skiing and find that it works well as my uphilling jacket for wind and light precip protection with a light base layer underneath. I often will forgo the downhill shell on warm days or when the descents are short and just wear the helium HD.
I plan to have this in the pack at all times this summer for alpine and rock climbs. I'll probably even carry it in addition to the full on waterproof shell for a little added protection in full on rain.