I'm conflicted. My wife and I bought a pair of iPhone 5S phones (first lightning devices), and I wanted some additional cables for charging/etc.
Save yourself grief and confusion by ordering from monoprice.com
I have both 3ft and 6ft cables; they work fine with my 5s. Connector ends fit the Apple Leather Case, so unless your other cases have smaller openings you should be perfectly fine. Monoprice publishes the connector size on their site so you can measure to check.