Since this book seems to be getting so much love, I think I'll crash the party and toss in my opinion of it, since I've worked my way about halfway through it by now. In case anyone is thinking of buying it, hopefully it can help them make a more informed decision.
This book has a ton of great sentences (it's basically just a book full of sentences), so it's great for finding stuff to add into your SRS.
However, I think this book is terrible for actually learning grammar from. I would only recommend this to someone who has already studied quite a bit of grammar. The reason for this, is that rather complex sentence patterns are used in the sentences before they are really covered in the book! It's incredibly odd to come to a section filled with sentences about a certain grammatical point, and to realize that they have already been using it in a ton of sentences prior! Perhaps just as odd, it covers some points multiple times. Also, there is basically *NO* explanation of the grammar itself. You pretty much just get the sentences along with an English translation. The translations themselves are not very literal at all, having been written in "natural" English. I think this takes away some from the ability to really understand what the Japanese is conveying.
Personally, this all didn't bother me too much, since I already had a pretty good grasp of grammar and just wanted the sentences. If I was just starting out though, I think I would be really confused by this book!