As usual, Motorola lets you to build a Moto X 2014 with a choice of 16GB or 32GB. But today, you are now able to select 64GB as new option for the Pure Edition and unlocked.
You may consider to select the 64GB option because the Motorola Moto X 2014 doesn’t support for micrSD card to expand internal storage.
At this moment, the 64GB option is only available for the Moto X 2014 Pure Edition which price started at $599, contract-free. The Moto X Pure Edition is working on both T-Mobile and AT&T networks.
So if you are interested in the Moto X and want to have one, pick the Pure Edition because it gets faster updates (it’s able to upgrade to Android 5.0 Lollipop now) and you can use with any carriers.