Overall, it's a good story. My complaint is that sometimes it really feels like it drags on and on and on and on... It doesn't flow the best and even with its humor, I did sometimes wonder why I was still reading this book. A lot of times, I had to wonder what the point of things were (which is probably the author's goal) and how many pages I had left before it was over. But, since I wanted to know what happens in the end, I kept going.
This is the fourth book of the Hitchhiker trilogy. Yeah, I know, that sounds stupid, but you have to know the series. This was more readable to me than the other ones. It seems to be more coherent and the cast of characters doesn't get lost. It's not bad. And if you like Adam's work, you'll love it. Just wasn't for me.