Thats actually a good question. And having seen both EPCOTs Illuminations and MK's Wishes many many many times, i still can't decide which i like better. I would say that Wishes is more crowded because it has limited viewing locations, while Illuminations can be seen all around World Showcase which is larger if you were to view Wishes from Main Street or somewhere else. My advise, get to wishes 20 minutes before it starts and do the same for Illuminations as both will fill up quickly. I like the music better for Illuminations. You will have to decide for yourself which you like better. Have fun and good luck!