With such addictive, ultra-hooky gems as the swaying "City Girl" and the amped-up "Under Water," this Canadian sibling duo fully delivers here on the promise of its U.S.

With such addictive, ultra-hooky gems as the swaying "City Girl" and the amped-up "Under Water," this Canadian sibling duo fully delivers here on the promise of its U.S. debut, 2000's This Business of Art. Actually, the group does more than deliver; studio-slick in all the right ways and uncommonly strong throughout ("Don't Confess," the set's last song, is one of its best), If It Was You is a near pop-rock masterpiece. These perfectly performed and captured cuts are masterfully spiced with a handclap here, a surprising and subtle banjo there, and sweet backing vocals all over the place—proving that the Vancouver-based Quinn sisters and producers John Collins and David Carswell have priceless pop sensibilities. Part of what makes If It Was You so irresistible is that Tegan & Sara deliver mature songs while not losing a tad of their youthful energy—and occasionally flashing a bit of angst. While seeming to have fully developed their own voice, the Quinn sisters have clearly given us one of the best albums of the year.—WO