The alpha numeric two letter codes of Chinese cities are desired. Its why you see JS and SS as the first two letters selling for more money than other names. Its why you see JS5387 sell for $500 plus. This chart I found does as good of a job listing the two letter city code for each major city as well as population size to give you an idea of which ones may be more popular. Many people are buying 5L.coms using these city codes as the first two letters. I haven’t really used the codes in my name purchasing but after looking at it I can definitely see some correlation in sales prices of some names. Especially BJ and JS.
Courtesy of Statoids