They don't have google. Baidu does not compare, not the slightest bit. Yes, they have bing. Try finding an address at bing (or baidu) maps in China. It does not work 50% of the time when google is right on the spot.
XiaoMi? Yes, some nice hardware. But the software comes from the west.
Not entirely. They use (or at least have used) mediatek chipsets. Their drivers... well, do a github search for mediatek chipset-based android source code. People have placed entire dumps of Mediatek stuff on Github... and the stuff I could find in 5min is SCARY. Fucking scary. And that's just the tools for the manufacturer, their kernel drivers are a mess of ifdefs and commented out code, with the sparse comments written in some Asian language.