I've found the data usage isn't that bad at all, it does however drain a good amount of battery but understandably so as your screen is on, data is on (Mobile data or WiFi), GPS is on and it is constantly generating 3D polygons. My phone gets quite hot too.
Complaining about the servers is unfair, as the game was only soft launched for certain regions, but people went ahead impatiently (like myself) and got it anyways. If people in Australia/New Zealand/USA want to complain, blame the Canadians, Africans, Asians and Europeans.
![Tongue :P](https://cdn.geekhack.org/Smileys/solosmileys/tongue.gif)