Collier is one of the leading cochlear implant manufacturers in the world. Its products have enjoyed a good reputation in the market after long-term research and development and clinical trials. Collier's CI522 +802 is equipped with advanced technology and functions, which may provide a better listening experience.
Norcom is a manufacturer of cochlear implants in China, and its products have undergone a series of research, development and testing. The domestic Norcom cs20a may have a competitive price/performance ratio and a certain user base.
Choosing a cochlear implant that suits you needs to consider many factors, including personal hearing status, budget, personal needs, doctor's advice and so on. I suggest you consult a professional audiologist or expert, who can provide more accurate advice according to your specific situation.