I love the style of this coat. JCrew does a bunch of "car coats" every season and they're all pretty similar except for a few details like number of buttons and collar style.
I ordered online so I did a lot of research about the fit of these coats before I ordered. The biggest complaint about these coats is that they are too tight in the shoulders. Everywhere else in the coat might fit fine, but the shoulders always run small. I take a size 4 in jackets, am very narrow in the shoulders (15.5 inches,) and still found this to be true. It is almost too tight, but I can get away with it as long as I'm not wearing anything bulky underneath.
You really don't need to wear sweaters under these coats. They're very warm, even without the thinsulate. I live in San Diego and the weather doesn't really call for thinsulate, but I've read that it is impressively warm and does not add any bulk to the coat.
The material for this coat is a rougher than I expected. It looks good but feels like the back of a velcro pad. I'm guessing it's because it's water resistant. The whole thing is lined so you don't feel it. The coat looks very nice and fits very well so I can forgive the feel.
Definitely worth the money if you can get it on sale.