Hmm depends on which genres I'd judge them on.
To me, I would say the best coin magicians are Giacomo Bertini, Kainoa Harbottle and David Roth since I love their techniques and they're the ones who inspired me the most.
But on the other hand, if I'd judge on performance, excluding the ones I've already mentioned, I'd probably add Eric Jones and Michael Rubinstein.
But if I'd stop being an over-analytic ass and get to the point I'd just say Giacomo Bertini.