hype-wise, zoro. because ryuma is probably as strong if not stronger than Roger.
practically speaking, sanji has the better deal since he just got a PU due to RS "unlocking" his DNA.
Long-term zoro wins because he will be the equivalent of not just mihawk, but surpassing him and becoming ryuma.
Short-term sanji wins because Oda has given him a PU instantly due to unlocking his DNA potential.