Few artists have their music repackaged as frequently or as frustratingly as Paul Simon and Art Garfunkel, who recorded five albums together before taking widely divergent solo paths in 1970. Those albums have been reissued, remastered, and reissued again, compiled on a box set with no bonus tracks (1981's Collected Works), compiled on a box set with bonus tracks but with album tracks omitted (1997's Old Friends), and now remastered again and compiled on The Columbia Studio Recordings 1964–1970, a box set with all the album material and 13 bonus tracks—some of which are unreleased, and some of which were included on Old Friends. Of course, Old Friends mustn't be rendered obsolete, though Collected Works sure is, so a handful of the Old Friends rarities remain exclusive to that set. The Columbia Studio Recordings wouldn't be frustrating if it weren't worth owning, both for its exceptionally clear new mixes and for its obligatory extras, most notably the three demo standards ("Barbriallen," "Rose Of Aberdeen," "Roving Gambler") tacked onto the end of the Sounds Of Silence disc. That convoluted caveat in place, the albums themselves remain excellent, albeit uneven. The duo's acoustic 1964 debut, Wednesday Morning, 3 A.M., feels a bit timid and over-polished, but its sparkling, reverent folk-pop remains underrated. A somewhat ill-fitting cover of Dylan's "The Times They Are A-Changin'" illustrates the minor identity crisis at work—the pair wasn't born to sing Dylan, as Parsley, Sage, Rosemary And Thyme's homage "A Simple Desultory Philippic (Or How I Was Robert McNamara'd Into Submission)" proves—but the initial incarnation of "The Sound Of Silence" is far from the disc's only highlight. An electrified version of that song helped make 1966's Sounds Of Silence the hit its predecessor wasn't, but the album itself feels rushed, and as a result is a bit of a shambles. Wednesday's mannered polish has been stripped away, but besides its unforgettable bookends ("The Sounds Of Silence" and "I Am A Rock"), the songs aren't quite there. Parsley, Sage, Rosemary And Thyme packs far more memorable material into its 28 minutes, opening with the beautifully arranged "Scarborough Fair/Canticle" and working its way through the likes of "Homeward Bound" and the guilty pleasure "The 59th Street Bridge Song (Feelin' Groovy)" before closing with "7 O'Clock News/Silent Night," a message song as heavy-handed as it is eternally effective. Bookends is Simon & Garfunkel's most musically and conceptually daring album, sampling the voices of old people ("Voices Of Old People") and opening with the dense clatter of "Save The Life Of My Child." But the 1968 album's hits ("A Hazy Shade Of Winter," "Mrs. Robinson," "America") are among the duo's best. Simon & Garfunkel split after the release of 1970's Bridge Over Troubled Water, but it wasn't for lack of sales: Bridge sold millions and spawned huge hits in the form of "Cecilia," "The Boxer," "El Condor Pasa (If I Could)," and the classic title track. The album itself suffers slightly from the songs' longer running times, in part because Simon & Garfunkel usually possessed a flair for brevity, but Bridge is arguably the duo's most cohesive, consistent record. The box set's well-publicized emphasis on previously unreleased bonus tracks sidesteps the fact that most are demos and alternate takes, and not exactly radical departures from their counterparts. Collectors not obsessed with hearing the albums' improved mixes may want to stick with the Sounds Of Silence disc (which, like the others in this set, is also available separately, with bonus tracks included) and leave the $50 box to those who haven't already splurged on its predecessors.