I've been looking for a very lightweight soft shell jacket for two years ... but everything I saw was either nylon (too clammy) or weighed a pound or more. This jacket is only 10 oz, highly water resistant, and it breathes very well.
I took it on the Teton Crest Trail in Sept (great to cut the chill in the mornings) and on several October day hikes in New England. It won't replace your rain shell ... but it's the most versatile article of clothing in my pack.
Love this tee so much I ordered two more. Great in both hot and cold weather.