my friend had one,here is the problems she faced
transcoder problem: when we make a call , the person who receives the call on the other side will only hear disturbance and not the voice.
call termination button: if you accidentally dial a number you don have choice to disconnect it as the end call (red button) doesn't work.
time display: it always shows the time which was set last time without changing.
internet:
though Nokia claims to provide Wifi, this phone doesn seem to connect
my opinion i still stick with my iPhone 4