Best Official Duos:
Run DMC
EPMD
Outkast
Organized Konfusion
Smifnwessun
MOBB Deep
Blackstar
Binary Star
Camp Lo
Punch and Words
UGK
Best Un-official Duos
Raekwon & Ghostface
Royce 5'9 & Eminem
This looks proper! I was wondering why nobody mentioned 'Kast or Rae and Ghost until this post, only other duos I can think of worthy of mention are Eric B & Rakim (if you consider GangStarr and Kool G Rap & Polo,..), Slick Rick & Doug E Fresh, London Posse, Heltah Skeltah, Artifacts (Tame & MC EL), Qwel & Maker, Siah & Yeshua, KMD, Latyrx, Blackalicious, Kataklizim (zimbabwe), Positive Black Soul (senegal) and FOKN BOIS (ghana),.. oh yeah and Robo & Omen (s.a.) from back in the day