XIA Class has 2 types actually. type 1, old one, the loudest nuke sub in the world; type 2, as 92G(G, meaning in chinese is improve).
so , I build 2 types of XIA class with different parameters: sound level; missile launch speed and depth limit;sonar;weapons;....etc, all base on reality and public knowledge
well, let the pictures speak
now, I'm hunting for good models for 093(SSN) 094(SSBN) YUAN class SONG class, it take times to build a navy. if you guys have useful resource, please feel free to enlight me