Unfortunately the 715 is in a bit of a state at the moment. Since it was announced it seems as though the low/high power versions colour schemes got mixed up when you're talking about EW/American models and since they came out patrolbase has had the exact same f*cking power readings for both models (I have mentioned this to them and was told that the readings were correct.
AFAIK; if you have the "low power" 715 you can use the normal shells. But seeing as there's not much solid proof laying around I haven't bought one yet.