Gwen Stefani, MEN Arena, Manchester<br/>Feist, Shepherds Bush Empire, London

In an unsubtle piece of symbolism, before the house lights fall and the show begins, the MEN Arena stage is draped in Blondie-inspired candy stripes. Gwen Stefani: maker of occasionally great pop singles? OK, we'll buy that. Gwen Stefani: the new Debbie Harry? She wishes.

But the house lights do fall, and for a moment the spotlight is off Stefani, right. The Sweetest Escape tour begins with a skit in which the Harajuku Girls – Stefani's quartet of Japanese female dancers – are pursued by searchlights up and down the arena's aisles to the strains of Costello's "Watching the Detectives", then arrested by cops, upon which Gwen herself is thrust into view, held captive inside a jail cell where she sings "The Sweetest Escape", her hit with the maddeningly catchy "woo-hoo, yee-hoo" refrain that you'll still be whistling when you go home.

This time, the symbolism is irresistible. Gwen Stefani, you see, has been tried and found guilty by the knee-jerk American media. Self-appointed spokespersons have condemned Stefani for perpetuating Western preconceptions of oriental women as servile and mute, and the Harajuku Girls themselves for being Japanese Uncle Toms.

Complaining about "political correctness gone mad" is the thwarted bleat of the bigot, but for once I concur, because the controversy surrounding the Harajuku Girls is a classic case of PCGM. For one thing, the complainants clearly know little about Japanese culture, particularly the country's bent for fetishising its most extreme aspects. For another thing, they miss the point of the quartet. Love, Music, Angel and Baby don't come across as anything less than empowered.

Defending Gwen Stefani does not come easily to me. If ever there was a case of hate at first sight, it was when I saw Stefani in the video for No Doubt's "Don't Speak".

On so many levels, Stefani is an irritant, to an extent that no amount of David LaChapelle cinematography or Pharrell Williams production can completely fix. Her fondness for sampling loathsome showtunes doesn't help, whether it's the March of the Gladiators circus music, Topol's "If I Were a Rich Man" (complete with fake dollar-bill confetti) or that bloody "Lonely Goatherd" song from The Sound of Music. And yet, despite myself, despite herself, she wins me over. The skipping-rope chant of "Hollaback Girl" still hits the spot, as does the irresistible momentum of "What You Waiting For?". And she walks it like she talks it, specifically the line "take a chance, you stupid ho'", delving deep into the crowd halfway up the slope of seats to sing "Cool". "I only got hit once," she says on the way back. "Thank you very much for that."

In her own small way, Feist has an equally impressive moment of spontaneous crowd interaction. During her show at Shepherds Bush Empire, a fan proposes marriage to another fan live onstage. It's a microcosm of Feist's career: the intensely personal made highly public.

It's not long at all since Leslie Feist was best known as a bit-part player in a defunct musical movement. She shared a flat above a Toronto sex shop with glam-punk gender terrorist Peaches, performed and recorded with her and fellow Canadian scenester Gonzales, and followed them both when they moved to Berlin to hook up with the emerging Electroclash movement. Her first three albums earned her a reputation as a quietly compelling singer-songwriter. It's her fourth, however, this year's Reminder, which is turning the 31-year-old's small company of rabidly adoring admirers into an army. It's been helped by the use of her song "1234" on an iPod television advert.

And therein lies the dilemma. If her fragile blend of emotionally naked lyrics and vintage American styles is exposed to the arenas stalked by Stefani, it will surely wither and die. Better book the Empire for a week next time.