Hotel is a weird series to write a review one, because it is actually a collection of short stories, each with their own degree of quality.
I've read my fair share of Boichi works, and for the most part I've come to the conclusion that while he is very good at drawing, he is not quite as good at writing stories to go with the art.
However, the first three chapters of this manga are, surprisingly, pretty good! This might be some of the best writing I've seen from Boichi.
Chapter 1 is a pretty cool story about this little AI that has the job of keeping all of life's DNA intact. It's postapocalyptic, and pretty well written. I'd give it a 6/10.
Chapter 2 is about a man and his soon to be dead wife. It's just a one shot, but it manages to pack a pretty cool story in the short amount of time. I'd give this a 7/10.
Chapter 3 is my favorite in this entire anthology. It's the story of a man who just so happened to eat the last tuna in the world, and his life's work trying to bring it back. It's funny, yet still deeply touching in a way. I'd give it a 8/10.
The last two chapters are, quite frankly, a mess. I don't really know what was going on there, or what Boichi was trying to do. I'd give them both a 2/10.
Adding this all up, you get an average score of 5/10, which I think is pretty much what this series is. It's a cool, short read that I would recommend if you want to just pass some time.