My first impression of this beer was "yummy." I like the label. The geometric prints make me happy and I feel like it stands out on the shelf. That's a big thing for me. If your bottle blends in, I'm not going to notice it or think to pick it up. I also really like beers that tell me what kind they are on the label. Bonus points for the fact this is a stout being clearly labeled.
Random life note: While getting this beer out of the fridge, I discovered the freezer wasn't as cold as it should be. I *hate* that.
While actually drinking this beer, and not staring at the label or swearing at my freezer, I found it to be a bitter at times. In the end, I would definitely drink this again. I don't know if I'd go on a hunting expedition for it, but I would definitely drink it whenever offered to me. And the ABV was high (about 9.1%) which is nice. Who doesn't love a beer with high ABV? Really by the end of the bottle, it seems like the beer was that much better.
Here's what Ninkasi has to say about their beer: Imperiale Stout
Here's what others think of this beer over at Beer Advocate.