I'm afraid I will start looking into Greek grammars for non-Greek native speakers in a few months, but a little bit of googling came up with nothing but praise for this book.
Some results by Greek sites I trust include
this, an exellent article from one of the authors
here (citing this grammar in the bibliography to boot), and
this which actually lists quite a few grammar books for MG (the last section, titled "3. Ξενόγλωσσες γÏαμματικÎÏ‚" lists some other Greek grammar books in other languages)
Note that I know the person posting
this list and his knowledge of Greek grammar is quite, quite good (I used to frequent that site till I got lazy

) Last but not least (there are many more results mind you) the Centre of Greek language (to which the first link also belongs) lists it
here as one of the books to be used to teach modern Greek as a second language.
The first of the links, one of the best around describes its authors as having both the knowledge and the experience for a succesful work.
The book belongs to the series of basic grammars (Essential Grammars) of the publishing house and is a compendious but adapted and finished of one of the more extensive grammars.
It is a simplified presentation (simplified in relation to an indepth analysis) of the modern language (written and oral speech) and is designed for beginners, adult English speaking people learning Greek.
The whole, rather long review ends by saying that in conclusion, it is the frst of its kind for beginners, containing all the basic ellements that these people can possibly need, written in a simple and easy to understand way with structure and presentation that make it accessible to its user. They also consider the bibliography at its end a very useful tool since it includes all the basic teaching textbooks, grammars and dictionaries that one can look for and study.
Edit: I've not included any English results since well, you can check them out yourself

Oh, and I owe you one for this.