Have you ever heard anything off of Infinite?
http://www.youtube.com/watch?v=CtRbEgoTqQs
It's probably as serious as you'll ever hear Em. It's before he picked up the whole Slim Shady gimmick. One of his best. Probably my second favorite of his. Marshall Mathers is 3rd, and Eminem Show 4th. Relapse.... I guess.... is 5th. The other 2 shouldn't even exist.
This is completely disregarding anything from D12 or Soul Intent though.
But yeah, check out Infinite, if you haven't yet, dude. It's raw, yet so, so, so smooth at the same time.