I've had two issues with Chinaphones in the past. One corrupted the SD card exactly 1 year after the thing was first switched on. In fact this happened to three handsets of the same model, as I'd purchased one for my gf and one for a friend at the same time. They all had exactly the same problem on the same day.
The other issue was a phone which, after a few months of use, started serving pop-up adds at random.
After that I never bought another Chinaphone again. There's really not much need these days, anyway, with so many perfectly serviceable brand-name budget phones available.