Great Fall/Spring Running Jacket!
This is made for high activity in cooler weather and it's perfect for just that! Looks great too.That being said, it's definately not good for standing still in cool weather, but it's not supposed to be. It doesn't have much weather resistance, but it's got excellent breatheability(it allows the wind to go thru w/out the bulk or heaviness of a fleece/sweatshirt)and gives a little warmth whenn needed. If you go exactly by the size chart,you'll be fine.I'm 5'7" 125lbs and wear this in a small- great fit and enough room for baselayer under. Love it!

Awesome Softshell for running!
I purchased this coat after realizing I need a breathable coat for trail running in Montana that was a little bit warmer than the Patagonia Nine Trails Jacket. This coat is minimalist, but perfect for runs on cool days. The fit is trim, but not tight, there are no pulls or tabs to adjust the fit on the bottom. The sleeves have a nice cuff for a snug fit around your wrists, and I like that the neck doesn't come up too high. There is one small side pocket for keys, iPod, ID, with a hole to put your headphones plug through. This coat does not have a hood which I actually don't mind. What I really loved is that this coat keeps me warm, but actually breathes. I don't feel cold and clammy wearing it. I am 5'7", 135 lbs and the medium fit well with enough room for layers underneath. The gusseted arms are nice, you can raise your arms without the coat riding up. If you want a coat that is not super lightweight nylon but still breathes and moves well, this is the coat for your future runs!

Exactly what I've been looking for...
I was searching for a really lightweight jacket for cycling and to carry in my pack on warm weather hikes where it could get chilly. This jacket fit the bill. An added bonus is that it also looks great on. I has a longer cut than the Celaris jacket, which I like. Fit is true to size with room for a thin to medium baselayer underneath.