I bought this jacket after Christmas & it has quickly become a staple item for me.
It's lightweight, & very breathable, so it's comfortable to wear on cool days (60s-50s). The Gore Windstopper makes it comfortable to wear on colder windy days too (40s).
It's not insulated enough to have as your only layer on cold days (30s and below). For example, today the high is 34 here in Raleigh, NC, & I'm wearing it over an under shirt, long-sleeve button-down shirt, & a vest.
But I guess this is also determined by what you think cold is.
I wouldn't suggest it as the top layer if you're in heavy rain or snow, as it's not waterproof. In light rain, it's fine, as the water tends to bead-up. On days in the snow or heavy rain, I'll usually wear a waterproof shell over top.
The fit is very comfortable, as others have mentioned, & it's also a little stretchy. I can easily layer another light fleece under it, with a long shirt & undershirt.
The fabric is not like other soft shells. It doesn't have that smooth sheen. It's almost similar to a very small corduroy pattern, with much smaller "valleys" than corduroy.
The extra features are what really puts this over the top for me. The inner cuffs with thumb loops are awesome. Think of them as almost half gloves. They're great to provide that little bit of warmth if I'm outside for a short walk. As someone else mentioned, you can also use them before putting on gloves to give extra warmth. Since they're inner cuffs, it also keeps snow or cold air from coming up your sleeves.
The sleeve pocket is great for stashing keys or other small items. This comes in handy when taking a run or light hike.
One thing the description doesn't mention is that the inner-pocket has a exit point inside, at the top of the pocket, for your headphones. Some people might have assumed this, but I just wanted to provide a little clarity.
I did a lot of shopping around before deciding on this jacket, & I think this jacket is one of the best deals for the price. I would highly recommend it.