cp wrote a review of Arc'teryx Gamma LT Softshell Jacket - Men's on January 3, 2010
This is a fantastic soft shell jacket if the specification fits you.
First, here is my take on how to buy a right Soft Shell jacket.
I break it down to two categories.
A) Use for trend the jacket will be only use for casual wear. These jackets are usually cheaper, heavier, less flexible/stretchable, warmer and most importantly it sports a wider/roomyier cut. This type will fits you fine if you are not built slim and dont do any strenuous exercise. Try to exercise with one of these and you will quickly overheat. The North Face Apex Bionic fits this category, inexpensive and sporty.
B)Use for outdoor activity the jacket will be much more expensive, lighter, has greater flexibility/breathability/stretch ability, and most importantly it sports a trim/athletic cut. This jacket will not keep you warm if you expect to lounge around unless you put some quality base layer(s). It will keep you warm and dry during the strenuous exercise and prevent from overheating. Meaning, it will have much more temperature range versus the trendy ones. Because of the high price, it is not likely become trendy. The examples are most of Arcteryx, some of Marmot, Mountain Hardwear, some of the North Face (like Sentinel/Valhalla jacket) and etc .
Now, lets talk about this LIGHT jacket. It has the athletic cut with longer back than the front. It has excellent breathability and stretch ability. Also, has the descent windproof/water resistant. Im 6 tall with 180lbs with 41 chest/32 waist and the Medium fits me like a tailored jacket. I love the fit and the color (Carbide). The temperature range is around 30F to 50F. Any higher temp, Id wear a vest on top of a base layer. It can be worn below 30 as long as the wind is not so high and I was able to test it today.
Three day ago, I wore this jacket with an Assos long sleeve base layer for an hour long run in the temp of 31F with light wind and it kept me very comfortable. Today, I went out running with the exact same setup. The temperature was in the mid to upper 20s but the wind was hauling at 25 to 35 mph (NW direction) with the gust reaching 45+. Thats when this jacket hit its limit. I couldnt stay warm to save my life. Only when I turned around (always run into the headwind in the winter when I start running) I was little comfortable. It definitely isnt a jacket for a single digit wind chill. I shouldve worn a Gamma MX, TNF Sentinel or little heavier/wind proof jacket.
Hope it helps you decide on a right soft shell jacket.