A few weeks before I started this blog, I kept seeing pre-order links for a bunch of catalogue titles from Universal Music Enterprises under the banner of "Rarities Edition." By the time the first batch of them came out in January, I had found out that the sets were essentially the bonus discs from some of UMe's unmistakable Deluxe Edition titles, priced to entice those collectors who wanted those bonus cuts on disc without purchasing (or re-purchasing) a more expensive set.

Now at first blush, these releases - which cover titles like Weezer's first record, Diana Ross' Diana, Marvin Gaye's What's Going On and a forthcoming set for Bob Marley's Legend compilation - seem kind of neat. After all, those Deluxe Editions can sometimes get expensive - usually $25-$30 for a new copy - and not everyone is infatuated with the idea of buying titles on CD more than once to get the best mastered version out there.

But when you really think about it, there are a couple of flaws inherent for some buyers. For one thing, despite the less expensive price tag, one of the biggest selling points of Universal's Deluxe Editions is that slick packaging. That plastic O-card. Those thick, four-panel digipaks. Liner notes that you want to read more than once. I have no clue if there are liner notes in these sets or not, although it wouldn't make sense since the album in question isn't there.

The other trick is slightly more deceptive: some of the Deluxe Edition titles have bonus tracks on the first disc as well. Sometimes these are worth the price of admission; keeping them out of a mid-priced rarities set is a bit of a gyp for the uninformed consumer. And even for the sets that have all their bonus tracks on the second disc, you'll still have to make sure you have a copy of the first disc proper. Otherwise, you'll have to spend the same amount of cash on two separate releases, which isn't as efficient to a guy like me.

So as a public service, I've established a bit of a buyer's guide to all the current and forthcoming Rarities Editions after the jump. Some of them are actually worthwhile if you've missed the Deluxe Editions, but more than a few are sorely lacking.

Marvin Gaye - What's Going On (Motown, 1971)

This set is indicative of the classic problem befalling a few of these Rarities Editions. The excellent Deluxe Edition of this LP added a live show, single masters and an entirely unused mix of the album between the two discs. The physical version of this rarities edition only has the second disc, thereby denying buyers that other mix. The digital version has all the bonus content, but if you're not a big digital buyer (and I'm not), the actual Deluxe Edition is the way to go.

Howlin' Wolf - The London Howlin' Wolf Sessions (Chess, 1971)

The bonus disc from this deluxe set had simply more material from Howlin' Wolf's famed sessions with Eric Clapton, Charlie Watts, Bill Wyman, Steve Winwood and company. The first disc had three tracks from another LP, London Revisited. Smartly, the Rarities Edition included all that bonus material, making it worth your money if you don't have the Deluxe Edition.

Lynyrd Skynyrd - Street Survivors (MCA, 1977)

The bonus disc that accompanied the last Skynyrd LP before the plane crash had a load of alternate recordings, demos and live cuts. But they were all different from the bonus tracks on the 2001 CD reissue. If you skipped the Deluxe Edition for some reason, here's your chance to get these tracks on their own.

Diana Ross - Diana (Motown, 198o)

This Rarities Edition functions as a clearinghouse for rare and random Diana Ross dance tracks predating the release of Diana itself. Besides the tangential connection to the source material in question, the physical edition of this set is sorely missing the alternate mix of the album by producers Nile Rodgers and Bernard Edwards that was on the first disc on the Deluxe Edition. (However, that mix is present on the digital Rarities Edition, if you're so inclined.)

Motorhead - Ace of Spades (Mercury, 1980)

The bonus disc on this deluxe set had a B-side and some alternate and live takes included entirely separate from the original album on the first disc. That said, the 1996 remaster has the two tracks Motorhead did for a split EP with Girlschool in 1981, so if you pick up the Rarities Edition, try to get that reissue in the process.

Rick James - Street Songs (Gordy/Motown, 1981)

The bonus disc of the Street Songs reissue is a killer unreleased live set from the summer of '81. While there were four bonus cuts appended to the end of the first disc - 12" remixes and instrumental B-sides of "Super Freak" and "Give It to Me Baby" - there was a single-disc remaster released around the same time that also included those tracks, so they're not only exclusive to the Deluxe Edition. And if you don't need those remixes on a physical format, the digital version of this Rarities Edition title actually includes them as well, which is a nice gesture.

Dexys Midnight Runners - Too-Rye-Ay (Mercury, 1982)

What makes the Rarities Edition rather screwy is that the Deluxe Edition this disc comes from is itself missing bonus tracks included on other reissues of the album. A 1996 reissue (the one with a green border on the cover) had eight B-sides added to the end of the album; another reissue in 2002 included five bonus tracks, two of which had been on the last reissue. The Deluxe Edition in 2007  had a bunch of BBC live tracks on the second disc, but had another seven bonus tracks on the first disc, five of which had ended up on the previous reissues. (Confused yet?) The rarities edition, to be released March 9 digitally, looks to include all of the second disc of the Deluxe Edition and four of the seven tracks from the first disc. In such an event, perhaps it's best to spring for one of the reissues on their own - after all, they're the discs that'll have "Come On Eileen" on it.

Bob Marley and The Wailers - Legend (Tuff Gong/Island, 1986)

The bonus disc to this bestselling compilation, with all the extended remixes one can stand, is fine enough on its own. The only extra track on the first disc, the non-LP "Punky Reggae Party," was included on the single disc reissue of the set in 2002 and the deluxe version of Exodus, so it's not impossible to find.

Eric B. & Rakim - Paid in Full (4th & B'way/Island, 1987)

A worthy purchase if you've already got the album, as the 12" remixes on this disc are safely isolated from the proper LP on the Deluxe Edition.

Steve Earle - Copperhead Road (MCA, 1988)

This disc of live cuts is also worthwhile if you haven't got the Deluxe Edition, since there's no other bonus content on the first disc.

Gin Blossoms - New Miserable Experience (A&M, 1992)

This was a blink-and-you-missed-it deluxe title for whatever reason, but completists are going to want to spring for that version over the Rarities Edition, which omits three tracks present on the bonus disc of the double-disc set (the first three cuts on the disc were from the band's independent LP Dusted from 1989). Worse yet, you can't buy those tracks on their own in iTunes or Amazon. Lame!

Weezer - Weezer (Geffen, 1994)

The Deluxe Edition of the band's debut LP kept all the extra content on Disc 2, entitled Dusty Gems and Raw Nuggets in the liner notes. They include pretty much all the B-sides from the Blue Album period, a handful of demos and the original LP mix to "Say It Ain't So" (replaced with the single remix on later pressings). The Deluxe Edition has some sweet liner notes but if you don't care, this one's a pretty good buy.