Canada版

You should be able to use the iPhone 6 without issues, except:

1. When you are using China Mobile (Hong Kong or Mainland)

2. When you are using any Chinese carriers in the Mainland.

The Canadian version does not support TD-LTE. You will not have 4G coverage when any of the above apply.

2014-09-28 06:10:21 補充：
It depends on how much you will pay.

If you pay full price, your phone can be unlocked immediately. Otherwise, it is locked to the carrier.