Come on now, AZ's verse on illmatic is one of the best guest verses of all time lol...I know you like going against the grain but I'm not falling for the troll.
his voice has nothing to do with the quality of his verse tbh...AZ was better lyrically, his melodic and multisyllabic cadence immediately impressed on the first listen and dude said way more things than Nas with only 16 bars.