i don't think there is a 'king' all those mentioned above have all produced excellent 303 based tracks but so have a lot of other people. Alot of the greatest tunes in my opinion have been collaborations trying to pick one producer who's the best seems impossible to me: depends what mood i'm in, some days i can't keep away from routemaster other days i prefer the smitten vibe, tomorrow i might just rinse geezer stuff do you know what i mean.

A mix of all my favourite 303 tunes would probably contain a fairly even mixture of producers!!