Twenty-five years, 10 albums. For U2 it's always been about the quality rather than the quantity of its music.

As a longtime fan of the band, through the years I've listened to U2's collective body ofwork, including B-sides, charity singles and bootlegs, innumerable times.

With the band going through a much-deserved revival -- courtesy of its best album in years -- and playing in Las Vegas on Sunday, I thought it time to revisit the U2 catalog.

After repeated listenings and much consternation, I've ranked the band's studio efforts -- including the live-studio-hybrid "Rattle and Hum."

For some reason I thought this side project would be easier to put together than the main story about the band. I was wrong, as I often found myself at odds with my own choices. ("You're putting 'Unforgettable Fire' ahead of 'War'?!?! Are you insane?!?!")

And even as I skim over the list a final time, I remain flexible on many of my decisions. Maybe that's a testament to the band's consistency. Maybe that's a sign as to how great most of these albums are. Or, maybe it's because I'm a boob. You decide.

At any rate, here is my ranking of U2's top albums:

1. "The Joshua Tree," 1987

Sure, it's like choosing "Sgt. Pepper's," "Exile on Main Street" or "Who's Next," but "The Joshua Tree" is a landmark album in its own right and made U2 "the biggest band in the world." Both poignant, epic and self-assured, the band's fourth studio effort packs an
emotional wallop on songs such as "With or Without You," "Mothers of the Disappeared" and "Running to Stand Still." It also features anthem-rock with a heart, such as "Where the Streets Have No Name" and "Bullet the Blue Sky." The band's apex.

2. "The Unforgettable Fire," 1984

Call it a sentimental choice, but "Unforgettable Fire" remains the band's undiscovered classic. Sure "Pride (In the Name of Love)" is probably U2's most recognizable tune, but other than the haunting "Bad" -- a song that's served even better live -- and the title track, radio avoids this album like the plague. It's a shame, too. There's a lushness and depth to "Unforgettable Fire" that seemed to hint at things to come but, sadly, never came to pass.

3. "War," 1983

The album that launched U2 and earned the band its socially conscious reputation, "War," in its best post-punk sneer, remains rough around the edges. Still, the band was clearly progressing as musicians (The Edge in particular) and Bono as a lyricist. Thanks to MTV and an astounding concert feature ("Live at Red Rocks"), "New Year's Day" and "Sunday Bloody Sunday" turned into career-making singles for the band. But it's the mournful "Drowning Man" that remains a personal favorite.

4. "Achtung Baby," 1991

Forgetting the ill-conceived and unrewarding "Rattle and Hum" project, U2 had a powerful one-two punch in "Joshua Tree" followed by "Achtung Baby." Recorded in Germany, the album showed a band no longer content to crank out the anthem-rock hits it had mastered so well; instead, U2 pushed itself musically with quirky pop songs "Mysterious Ways" and edgy --
by U2 standards -- rock "Zoo Station." The record is an emotional roller coaster, as Bono and Co. bounce from tripped-out to melancholy to happy-go-lucky and back again, but it's well worth the ride.

5. "All That You Can't Leave Behind," 2000

U2 at its best: humble, focused and hungry. After the disappointing "Pop" and its even more disappointing tour, the band's reputation had clearly taken a beating. Many U2 fans resisted the electronic-minded direction the group seemed to be taking. The band responded
with an album that musically fits neatly between "Achtung Baby" and "Joshua Tree." The album's first single, "Beautiful Day," is the best U2 song in years, and "Walk On," in light of recent national tragedies, is taking on an even more meaningful connotation.

6. "Boy," 1980

Smart, ragged and raw, the tools were all there, but U2 was still learning to use them. Nevertheless, there's a great deal of fun to be found on "Boy," especially on "Out of Control" and "The Electric Co." While the album lacks a true single -- other than "I Will Follow," which the band revived for its recent tour -- there's a cohesive quality to "Boy." As a result this is a record to take in on one setting, as many of the songs, such as "An Cat Dubh" and "Into the Heart," function better together than apart.

7. "Zooropa," 1993

The band's attempt at being loose and uninhibited often feels like a concept that needed more time to flesh out. Originally just a single, which turned into an EP and finally into an album, "Zooropa" was written while the band was touring with "Achtung Baby." There are some highlights, the trippy title track is fun and "Stay (Faraway, So Close!)" is "Achtung Baby" all over again. But "Numb" is still annoying and "Daddy's Gonna Pay for Your Crashed Car" was one album too soon. Kudos for the Man in Black on "The Wanderer."

8. "October," 1981

Bleak and bare, as on the album's musically minimal title track, "October" is the band's darkest effort so far. There's even a murky quality to the biggest single off the record, "Gloria," the band's nod to fellow Irishman Van Morrison and his classic tune of the same name. The story goes Bono lost the lyrics to the songs while on tour in the United States and penned many of the tracks -- including "Gloria" -- rather hastily while in the
studio. Not sure if it shows.

9. "Pop," 1997

Perhaps overly maligned by some critics and the general public, "Pop" remains U2's great experiment, as the band shed the shackles of traditional rock for the continued liberation of electronica. "Pop" has its moments -- "If God Will Send His Angels" and "Staring at the Sun" -- but more often than not the record misfires -- "Discotheque" and "Miami." Oddly enough, "Please," which is a passable album track, translates into a wonderful live effort, courtesy of some emotive guitar work from The Edge.

10. "Rattle and Hum," 1988

Just before the band launches into "Helter Skelter" Bono rather brazenly states: "This is a song Charles Manson stole from The Beatles. Now we're stealing it back." Maybe the song's inclusion is an acknowledgement by U2 that "Rattle and Hum" is an attempt at "Let it Be," mixing live tracks with studio work. Regardless, the results are widely uneven at best. Most of the concert recordings feel oddly flat and few studio efforts, save "All I Want is You," ever seem above B-side material.