http://edition.cnn.com/2017/03/25/asia/hong-kong-chief-executive/index.html
Both of the main candidates belong to pro-Beijing. It indicates it's impossible to criticize China as a governor of Hong Kong. Though Woo Kwok-hing is a candidate who is not in pro-Beijing group, he is excluded from the expected territory governor.
And, John Tsang is the realistic candidate for Hong Kongers to choose better one of the two, because the rival Carrie Lam seems to succeed the current CY Leung's political way, which is not favored by Hong Kongers. In a democratic country, Tsang will be superior to Lam. But, the election is held secretly and the final decision depends on Beijing government. Then, it will be difficult for Tsang to win without swearing loyalty.
If Lam were to be elected, continentization of Hong Kong will be advanced.