Here is a sampling of what they had to say:
Eric Grode in his Broadway.com Review: "John Lennon is not crucified in Lennon. That would be too bold, too dramatic a choice for a musical as rudderless as this one. Instead, he meets a sadder fate. He is simplified, defanged. He is turned into Everyrebel, a hunky martyr in granny glasses. Don Scardino and Yoko Ono Lennon now know it ain't easy to develop a compelling or even coherent piece of theater out of his music. And Christ, so do we... Only [Will] Chase, who looks and sounds the part, has any real success replicating Lennon's galvanizing charisma. Julie Danao-Salkin is OK as Yoko, and Marcy Harriell knocks down the theater with a ferocious rendition of 'Woman Is the Nigger of the World.' Beyond that, talents like Mann, Chuck Cooper and Julia Murney making a long-awaited Broadway debut are completely wasted... [Lennon] is a reductive, repetitive mess, a show without a glimmer of the mischievous, gentle wit that made Lennon's countercultural message so appealing to such a wide cross-section of listeners. The collaborators' love for John Lennon's words, music and aura is palpable throughout Lennon. Love is not all you need."
Ben Brantley of The New York Times: "Mr. Scardino and Ms. Ono whose name appears in large type in the credits, where she is accorded 'special thanks' have said that using five actors to portray Lennon reflects the idea that the man meant different things to different people. Yet instead of making Lennon seem multifaceted and multiform, this device turns him into a one-size-fits-all alter ego to the world... And because one of the actors, the charismatic Will Chase, looks and sounds much more like Lennon than the others, your focus is magnetically pulled toward him in ways that upset the show's balance... While the songs' musical hooks may still dig into your memory, the image of the man who wrote them is likely to feel fuzzier after the show than it did before."
Clive Barnes of The New York Post: "It benefits from its nine-person cast, superb from top to bottom, and, let's face it, expectations so reduced as to be almost minimal. It suffers from a concept and book by the show's director, Don Scardino, that is so shaky it can scarcely stagger from one side of the stage to the other. You also constantly feel that the show is positioned between a rock and a hard Ono. This is more hagiography than biography--a grayish whitewash of John Lennon's character, who appears heroically bowdlerized."
Marilyn Stasio of Variety: "Buy it or not, the theory of focusing on Lennon's solo efforts results in a score that sounds unfinished in a sad and rather ghoulish way. In particular, the songs in act one come across as a cut-and-paste job, lurching from disappointing cover songs 'Money,' 'Twist and Shout' to curiosities like 'Mother' written during primal scream therapy to unpublished work 'India, India' that proves to have been no great loss. Staging the show as a rock concert--with a 10-piece band onstage up to their knees in the clutter of amps, speakers and gnarly electrical connections--juices the sound, but does nothing to disguise the modest quality of this early solo material. In the same way, the exhibition of dancing follow-spots is a lot livelier than the foot-dragging choreography."
Michael Kuchwara of The Associated Press: "The ads for Lennon, the benign new musical celebrating the life of pop superstar John Lennon, proclaim: 'His words. His music. His story.' What seems to be missing, though, is the man himself--and any sense of theatricality. Instead, what we get is a bland stage biography, much of it recited directly to the audience, while a hardworking cast does its best to sell more than two dozen of Lennon's songs, a majority of them from the post-Beatles era... The show, which has the band on stage behind the performers, is never given a chance to build dramatically. Each song rises or falls on its own, giving the evening a jagged, uneven momentum. Yet, even with those limitations, there are some special musical moments. Among the more potent numbers: Chuck Cooper delivering a commanding version of 'Instant Karma,' and Julia Murney singing 'Beautiful Boy,' a wistful appreciation of young Sean Lennon by his father."
Elysa Gardner of USA Today: "Suggesting that the Fab Four was some inconsequential pop act that provided Lennon a stepping stone to his true calling is as unfair to him as it is to the other Beatles. They come off here--in that chunk of the first act that they're acknowledged at all--as a buffoonish boy band... Ono, in contrast, is revealed as a visionary worthy of her partner. And as played by the lovely Julie Danao-Sulkin, this Yoko is so surreally virtuous, so patient and noble... Lennon's title character is portrayed in turn by actors of different genders, races and ethnicities, a conceit that reinforces how his music and activism embraced the scope of human experience. One questions the point, though, of casting a woman as Elton John, or having a black man appear as Ed Sullivan and segregationist Sen. Strom Thurmond, beyond seeking a subversive or comic edge.There are, thankfully, a number of playful flourishes in Lennon--including a joking reference to Ono's, um, controversial singing voice--along with genuinely moving moments. But when you imagine all the people whom Lennon's songs and spirit touched, you can't help but wish him better."