Rappers wouldn't be anything without production.
Many times, production actually MAKES the rapper.
Got me to thinking who would be the Top 5 producers in hip hop.

I'd go with:

(in no particular order)

Primo
Battlecat
Daz
Dre
Quik


I can easily name 15 more that could easily take the spot of one of these five.
Shit,
Kanye
Timbaland
Dilla
Missy
Large P
Rza
Diamond D
Prince Paul
Neptunes/Pharell