I own that very same coat from SportsmansGuide, and I can say it is fully suitable for winter use anywhere you'd want to be outside in North America. There is certainly no cardboard used in its construction. The last one I had lasted me daily winter wear for over six years. Anyhow, they have a generous return policy, so if you don't like it, send it back - no reason to pay more for it.
Well that's very good to hear. I must have had a different one then (tho it did look the same). Mine was not suitable at all.