Only Slaughterhouse track I truly love is the Move On Remix. Despite the boring hook, everything is fire, every verses are great (Royce's especially)
https://www.youtube.com/watch?v=nnnRt9scg9M
Beside this one I'm not a huge fan of them, I like some songs, I don't care about the rest, but I'm deeply convinced they have the potential to be great. Like InsaneTRex said they're just too fucking lazy. I still think Em + Yelawolf + Slaughterhouse could be the Shady dream team, if Slaughterhouse shined a little more and actually tried to entertain
So anyway
Em - 9/10
Yelawolf - 9/10
Slaughterhouse - 5.5/10
D12 - 6/10 (based on the tracks that leaked in 2011, probably the last time they collaborated before Shady XV. 1999-2003 D12 would be a 8.5 I guess)
BME - 7.5/10 (based on H:TS)