I've consulted it many times over 33 years but only now read it through. Lots of interesting information. Probably overdue for a revised edition by now.
I owe this book more than I'll ever be able to repay. It helped me to love and enjoy Shakespeare even more , and it also helped me to get better marks in my university career (and some fo my friends' too- it was often borrowed) In fact it led such a harsh life I had to throw the tattered copy away and buy a new one, which I lined this time. (now I have an e-copy)Even if sometimes it is a bit snobbish (not including Kenneth Branagh, for example, who is despectively alluded to in the Henry V entry) and repetitive, it remains a highly valuable tool for students and Shakespeare lovers. Plays, characters, actors and actresses, theatres, productions, critics- everything is here.
This is an encyclopedia resource. As with any encyclopedia, entries are mostly condensed; one gets access to a large array of topics on Shakespeare. This book does provide some extensive information on each plays, namely, a scene by scene summary, an analysis, a list of its sources, and a history of its production. The value of this work depends on how much reference you need to investigate and also how much you can find better elsewhere.