Wifi broken, incredibly slow charging, and more problems...
Conclusions: From first power on it does sometimes flicker the backlight of the LCD which is really buggy and ugly. Only happens sometimes for some minutes though.
Wifi seems broken, which is something a modern phone cant do without and why i need to buy another phone. It did/does sometimes work, but for the last weeks not any more. Wifi connects, but is unable to acces to the ethernet.
Battery is a drama. It does indeed have 4000mAh, but it charges only about 0.65A at 5V, therefore it takes forever to charge