There are some threads about the different websites to book air travel in China, but nothing recent about 9588.com. Does anyone have any recent experience with this website?

I want to fly PVG-XIY on July 26 in the morning. Of travelzen.com, ctrip.com, and 9588.com, 9588.com is the only one that is giving me one remaining seat at a significantly cheaper price, so I am leaning towards them.

Any advice? Is it still too early to buy tickets for July 26 and a flight XIY-PEK on July 28?