It certainly didn't come off as an Imperial Stout to me. Too thin, didn't have that molasses and chewy backbone, and the overall flavour was far too weak for what an Imperial Stout should be. The ABV was pretty low too, BUT very apparent due to how thin and low carbonated the brew was.
Worst of all, I was getting a really salty taste coming off of each sip. Did you encounter that as well ?