I'd second IceAddict - I had the Nanook for a few years and I actually did really like the shack. I used it primarily as a 1 man and it was comfortable and warm. But that thing was a beast to pull by hand. The shallow sled acted more like a plow. I don't know how the bigger otters pull, but my XT hideout is 60# and I can pull that with ease.
Outside of being a pain to pull, I think the Nanook is a solid flip over considering the price. A smitty sled could fix the pulling issue if that's a deal breaker.