I bought this edition of Marlowe's plays for a Renaissance Literature course at uni, expecting a wealth of notes and annotations to explain social and historic contexts. I was quite disappointed to discover that the notes were very meagre and the only aspect of the plays that is covered in the notes is the mythological references. I think Marlowe is a brilliant playwright, but without a good edition you miss so much of the Renaissance thinking that went into his works.
The Penguin edition is not all negative, however; the editor explains the existence of the two versions, basing his edition on the 1616 B text, providing an Additional Notes section in which uses of the A text are given. Both versions of Act v scene i (the Old Man's Speech) are presented, though sadly not adequately discussed.
I'd recommend this only to people who don't like to be distracted by looking at the Notes at back of the book. If you're interested in the thought and influences on Marlowe and his work, you'll need a more academic edition.