Yiwu OEM Plastic Factory vs. Guangzhou vs. Shenzhen: Where to Source in 2026However, assuming these cities are interchangeable is a costly mistake. Each region has evolved a distinct manufacturing DNA. Choosing the right city in 2026 depends entirely on your product category, scale, target margins, and custom OEM/ODM requirements—especially when partnering with specialized direct manufacturing factories like DAQIDA in Yiwu.