depends what you want the phone for, ive just had the same dilemma, but i only use the phone for calls, texts and the camera, so i picked the D900, tbh my old N70 was a better phone as far as what it could do, but i didnt use half the stuff on it. i think the k800i is better phone than the D900 but like i say, the D900 its spot on for what i want, and ive loved mine since i got it.