Please do note that my five star review for Madeleine L'Engle: The Wrinkle in Time Quartet: A Wrinkle in Time / A Wind in the Door / A Swiftly Tilting Planet / Many Waters is NOT AT ALL about the actual contents and the specific thematics of Madeleine L'Engle's four Time Quartet novels. Because while I did read A Wrinkle in Time, A Wind in the Door, A Swiftly Tilting Planet and Many Waters in this here omnibus, in Madeleine L'Engle: The Wrinkle in Time Quartet: A Wrinkle in Time / A Wind in the Door / A Swiftly Tilting Planet / Many Waters I in fact and actually have reviewed each of the four books individually and as I finished with them. And therefore, if you go to the individual novels, you will be able to see and read my reviews for each of them, with A Wrinkle in Time receiving a three star rating, A Wind in the Door four stars, A Swiftly Tilting Planet once again three stars and Many Waters five stars (and with Many Waters most definitely being my hands-down favourite of Madeleine L'Engle's Time Quartet and probably after Meet the Austins my favourite L'Engle novel, period).
However, I do want to point out that if you are indeed interested in reading the stories Madeleine L'Engle has penned about the Murry Family and concerning their fantastical science fiction and fantasy imbued exploits and adventures in one all encompassing volume, you should in my opinion very seriously consider Madeleine L'Engle: The Wrinkle in Time Quartet: A Wrinkle in Time / A Wind in the Door / A Swiftly Tilting Planet / Many Waters (and no, neither the Murrys nor Calvin O'Keefe really play all that significant thematic roles in the four novels Madeleine L'Engle has written about Polly O'Keefe, with characters like Meg and Calvin O'Keefe generally simply textually existing and that the twins, that Sandy and Dennys Murry also very briefly appears in A House Like a Lotus, so if you want to read about the Murry Family in any amount of specific detail, well, you totally do need to read the four Time Quartet novels for that).
So yes, with regard to Madeleine L'Engle: The Wrinkle in Time Quartet: A Wrinkle in Time / A Wind in the Door / A Swiftly Tilting Planet / Many Waters, not only does this omnibus feature all four of the Time Quartet novels unabridged and complete, the fact that editor Leonard S. Marcus has also decided to add an informative timeline about Madeleine L'Engle's life, notes on the featured stories and a number of interesting articles (essays) penned by L'Engle about her work and how she views the universe, for and to me, this totally and majorly increases the reading pleasure and interest value of Madeleine L'Engle: The Wrinkle in Time Quartet: A Wrinkle in Time / A Wind in the Door / A Swiftly Tilting Planet / Many Waters exponentially and certainly does render me really happy and delighted to have read A Wrinkle in Time, A Wind in the Door, A Swiftly Tilting Planet and Many Waters in Madeleine L'Engle: The Wrinkle in Time Quartet: A Wrinkle in Time / A Wind in the Door / A Swiftly Tilting Planet / Many Waters and not separately, not individually. And honestly, truly, how Leonard S. Marcus shows and features Madeleine L'Engle: The Wrinkle in Time Quartet: A Wrinkle in Time / A Wind in the Door / A Swiftly Tilting Planet / Many Waters (and with all of the appreciated and wonderful supplementals), this all is certainly and spectacularly wonderful, superb and is in my opinion most well deserving of a five star rating simply and just for layout and set-up alone.