Oros Apparel Orion Parka The warmest jacket?

So I bought one of these jackets from an auction site for a little cheaper than it would have cost me to get otherwise. That being said I still spent 366$ to get the jacket and beanie. They boast to be the warmest jacket you'll wear, and they are. I found myself unzipped for a while and then when I felt I wasn't too hot I'd zip back up a bit. I work outdoors for hours in the film industry and spend about 12 hours a day outside. If anybody is thinking of buying a new winter coat. No matter what the size you're thinking you should size up if possible. I got an XL and it looks like I'll need a XXL but hey not complaining I'll give the other coat to my GF.