None.
From a commercial Rolling Stone magazine / American cultural perspective you can argue that the MMLP is a classic album. In the sense that it defined a period in time, the whole nation responded to it one way or the other. It did massive numbers. It was entwined with the Columbine massacre, homophobia, The Elton John thing, the Kim song, etc.
But from purely a hip-hop/music POV, it's not a 5 mic classic album IMO. Song for song you just can't say that MMLP is a classic like basically every other classic that's come out of hip-hop. Kim is an awful song. it might be shocking the first time you heard it, but it stinks. The Real Slim Shady is a goofy ass song.
You don't get to have awful and goofy songs on classic albums. The Kids is a corny song also. Under The Influence and Drug Ballad are cool, I guess. But classic songs? Amityville? Horror core, sure. Classic? Nah.
I'm trying not to hate too hard. There's dope and classic material on there. Kill You, I'm Back, Stan, Who Knew, bytch Please II, Criminal, The Way I Am...I might be forgetting one or two songs. But that's not a classic album.
And MMLP is the only Eminem album that you can argue is a classic. SSLP and TES are good, and so is Infinite. But no one should try to say they're classic. MMLP is Em's best and it ain't a hip-hop classic. It is a "timeless album" in the big picture of music in general, I'll say that.
I've never seen a minority riding around with his windows down bumpin Em's music aside from Renegade, and that doesn't count. His music had zero impact on the culture. HE obviously had an impact, being a white rapper, but his music? Nah.
EDIT: I saw this after my post and wanted to quote it. Yeah. There has never been another rapper in history that would've gotten a pass for 1/10th of the cringe worthy music that Em has made. There are Eminem songs I'm embarrassed to listen to alone. Forget other people around. If Jay or Nas had ever made a joint like Fack or Puke or Big Weenie or whatever the fukk they'd lose ALL credibility. yet for some reason, Em gets a pass on it, and is continually praised.
The one thing I'll say is that from a technical point of view he might be one of the sharpest and craziest rappers ever just in terms of flows/cadences/rhymes. But he's not very good at making songs or albums.