I'd always advise ordering ems/dhl I've heard it only takes a few days. I'm sure the phone won't lag it has a snapdragon 800 which is a insanely powerful processor. It also has a little over a 3000 mah battery so battery life should be good. Also the new processor is supposed to be very battery efficient. They put a 2300 mah battery in the nexus 5 which has same specs as the xiaomi mi3 so it should not need any extra battery Case. Xiaomi does sell a external battery pack for cheap they released not too long ago.
Now the phone hasnt been released yet. It was rumored to be out a few days ago but It might be a while cause so far I've heard nothing bout it.
And if you want it faster I'd say order other than ibuygou. They been taking preoders since September so theyve got to fill all of those before they get to sending out other orders so that's something to take into account. Another supplier that didn't take that many preoders the wait time would be much less.
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