Duets: The Final Chapter (Bad Boy, 2005) by The Notorious B.I.G.

On paper, this isn't a terrible idea.  However, in reality, it is.  Remixing a lot Biggie of verses from his two classics over "current" beats with "current" rappers contributing new verses just doesn't work.  It sounds fake and forced.  The only saving graces to the album are the songs with unreleased material.  "Whatchu Want" with Jay-Z and "Living in Pain" (produced by Just Blaze) with 2Pac, Mary J. Blige, and Nas are both descent records.  But they still come nowhere near making up for the rest of the project.

Recovery (Aftermath, 2010) by Eminem

This album was vital to Eminem's legacy and it did not disappoint.  In my opinion, it is his best album since The Eminem Show.  The material on the album balanced the clever, "just don't give a fuck" attitude ("Cold Wind Blows") with strong substance ("Talkin' 2 Myself").  Lyrically, Eminem proves again that he is one of the best writers ever.  And in perhaps his most emotional record since "Mockingbird", atop a sample from "The Lost Boys" and production from Just Blaze, Eminem pays homage to Proof with "You're Never Over."  Dr. Dre's only track "So Bad" is decent, but Just Blaze and DJ Khalil are the album's star producers.  Taken as a whole, Recovery was Eminem's return to glory professionally and evidence that he was able to make music that grew with him personally.

The Blueprint 2: The Gift & The Curse (Roc-A-Fella, 2002) by Jay-Z

This album does have too much filler, and could easily be cut down from a double album to a single one.  And there's "'03 Bonnie and Clyde" where Jay-Z and Beyonce take a Tupac classic [where his girlfriend is a metaphor for a gun] and make it a pop/rap record that, because of such a stretch, comes off as cheesy.  However, I can't fault the album for its approach.  Where the first Blueprint, sonically, focused on the past (i.e. where hip hop came from), this one wants to show where the genre can go.  The remix to "U Don't Know" featuring M.O.P. and "Show You How" are prime examples of refreshing and outstanding sounds, both courtesy of Just Blaze.  Jay-Z also demonstrates how hip hop can gel with other genres of music (i.e. rock- "Guns and Roses" featuring Lenny Kravitz and oldies pop which samples "My Way" by Paul Anka for the chorus).  Lyrically, the album also has some very strong points too.  Most notably, "Meet the Parents" where Jay-Z tells one of his most detailed stories ever and "A Dream" where he converses with the late, great Biggie Smalls.  Considering that this album is widely considered one of Jay-Z's weaker efforts, it is also worth noting that it is superior to most emcees greatest material.  Therefore, in addition to his best albums, Jay-Z is so good that even his "bad" ones can be used as evidence that he is one of the best emcees of all-time.  

The Dynasty: Roc La Familia (Roc-A-Fella, 2000) by Jay-Z

If I'm not mistaken, this album was originally supposed to be a compilation album in order to continue to showcase Roc-A-Fella's roster beyond just Jay-Z.  However, by making it a Jay-Z release, it probably helped it sell at least an additional million copies.  There are a few standout songs- "The Intro", "This Can't Be Life", "Soon You'll Understand", and "Squeeze 1st".  However, the highlight of the album, in my opinion is the production.  It was the first time I became aware of Just Blaze and Kanye stole the show with just his single contribution, "This Can't Be Life."  As far as the actual sound, in retrospect, it was like a blueprint to The Blueprint as far the beats beginning to dabble in the soulful sound that would help shape one of the best albums in hip-hop history less than a year later.