The Passenger, Lyric Opera Chicago, The Classical Review, Lawrence A. Johnson
"Nina Warren brought unhinged intensity to the Old Woman driven mad in the camp."

Marco Polo, Bergen Festival Norway, Financial Times (2013), Susan Nikells
"Tan Dun demands incredible vocal dexterity from his singers...Nina Warren is superb as Scheherazade"

Die Walküre, Buenos Aires Teatro Colón, La Nacion
"Nina Warren fue una muy buena Brünnhilde, desenvuelta en sus desplazamientos, de voz timbrada, sensitiva y refinada en el canto, muy emotiva en el decir"

Götterdämmerung, Teatro Petruzzelli di Bari, Opera Magazine
"Convincingly tender in the prologue. Her bright soprano coped with all the dramatic moments... and she was the linchpin of the evening, concluding with a remarkable Immolation Scene.."

Salome, Stuttgart Oper, Stuttgarter Zeitung, Horst Koegler
"...but the singers were beyond reproof, with Nina Warren, Stuttgart's latest American recruit, a Salome of astonishingly opulent sound and thrilling penetrating power."

Salome, Baltimore Opera Company, Baltimore Sun/Opera News, Tim Smith
"In the title role, Nina Warren ..the soprano rode the crest of the biggest orchestral waves sturdily and sang the long final scene with intense theatricality... Warren nailed the schizoid flavor of the scene with Jochanaan, writhing on the floor as she sang some of it, and in the Dance of the Seven Veils, choreographed by Sergio Trujillo, offered a workable combination of athleticism, grace and smut."

Salome, Salt Lake City, Dorothy Stowe
"Nina Warren showed a desirable clarion potential -- a clear, penetrating tone, strong and sure above the staff, and capable of bloom."

Fanciulla del West, Classical Voice Magazine
"Substituting for an ailing colleague at the eleventh hour, American soprano Nina Warren came galloping (flying, actually) to the rescue.  Given the lack of rehearsals or a prompter, Nina Warren's Minnie made a strong impression with her firm and powerful voice and an imposing stature that all but towered over Sheriff Jack Rance.   Her Act One solo 'Laggiu nel Soledad ero piccina' ended in a thrilling high B-flat."

Fanciulla del West, LA Times
"Her voice is healthy, sizable and handsome;..she delivered consistent beauty of tone throughout this long and taxing part, which demands ready resources of volume, lyricism and steel. And her acting as the Bible-reading, gun-toting Minnie who loves the outlaw Johnson proved credible and charming in every scene"

Makropulos Case, Cologne Opera, Opera Jamboree
"It was Ms. Warren's debut as Emilia Marty. Director Günther Krämer's staging seemed to capitalize on Ms. Warren's abilities. Her portrayal laid bare the many aspects of Marty's contradictorily fragmented, demented, and distorted personality: her cold eroticism, her desperate egotism, her sadistic cruelty, but also her sentimental longings and her now-only-fleeting gentle moments. The pathos and timbre in her voice reminded me somewhat of the Callas sound, especially in the introverted parts of the first Act. On the other hand, the pitch of her voice is similar to Nilsson's and I think her voice is no smaller than that of Ms. Nilsson."

Wozzeck, San Diego Opera, San Diego Magazine/Opera News, David Gregson
"American soprano Nina Warren, however, made the most of the vocal-cord-devouring role of Marie."

Der König Kandaules, Buenos Aires Teatro Colón, Opera News, Eduardo Arnosi
"...soprano Nina Warren, whose solid beauty of voice and body make her an ideal Queen Nyssia."