I could never fukk with Quik's rapping style, I've given him plenty of chances and even copped Safe & Sound but he just doesn't cut it for me. His delivery is weak as shyt. Dope producer though.
Best rapper / producer to me probably would be Kanye as he has had moments where he has been top tier in both aspects and has had success producing outside of his own work. My personal favourite is Dre, but you can't really credit him as an emcee as he's only got 2 albums and doesn't write his own ish.
I think Havoc and RZA deserve a mention. It'll be interesting to see how Cole, Krit and Mac Miller's careers progress though, both have talent on the boards and on the mic.