Dana and Mantey's Manual Grammar is a standard intermediate-level Greek grammar, utilizing the eight-case system of Greek verb classification. For those who have had at least one year of beginning Greek.
I would give this book 2.5 stars, but definitely not 3. It is useful as a reference if you need an intermediate level grammar based on the 8 case system, and does contain plenty of useful information. The reason it gets the low rating is because it is so biased in its presentation of Greek Grammar. The book is much more prescriptive than descriptive in its presentation of grammar. Dana and Mantey demonstrate either a profound ignorance of Indo-European Linguistics (even for their time), or are too concerned with being good Baptists to teach the subject well. Their treatment of the subject basically formed the basis for cottage industry of "8 case bashing" that occurs in New Testament Greek Circles. Unfortunately, this is the only option I know of if you are continuing into Intermediate Greek after learning the basics from W.H. Davis' "Beginner's Grammar Of The Greek New Testament". A.T. Robertson's "Grammar of Greek New Testament in the Light of Historical Research" is a much better work based on the 8 case system, but more advanced, and is still used for reference by today's N.T. Greek teachers.
Probably the best thing to do if you are teaching yourself Greek at the intermediate level is to use this book together with "Greek Grammar Beyond The Basics" by DB Wallace. Also, reading "Linguistics For Students Of New Testament Greek" by David Alan Black prior to beginning your intermediate-level Greek studies will allow you to get through Dana and Mantey unscathed.