After going though the testing of the 5S I notice the PPTP and L2PP work but the Checkpoint Mobile VPN and OpenVPN does not work on the iPhone 5S, oddly it does work on the iPad2 (Wifi) Which do have iOS7 also.
I've read its something to do with the new 64bit arc in the 5s.
Supposedly their working on it but who know how long it will be. Their kind of very slow in responses on their forums