In terms of the guests I've seen. Chinese anime conventions get some pretty impressive guests compared to U.S. counterparts of the same size. In just the last year I've seen Love Live cast members, Leiji Matsumoto, a few people that were also at the Anison event in Vegas recently, Kotoko, and a few probably notable people that I don't recognize or care to be familiar with. I would have been able to go to the star studded event that Bilibili puts out a few times a year if it worked with my work schedule/budget better. Bilibili is kind of China's equivalent of Crunchyroll+Youtube and they do a streaming video stage thing at conventions that puts Crunchyroll's to shame.
All that and Comiket is much closer too.