So apparently the P4's controller is the weak link when it comes to people getting any distances worth talking about. Now I see people talking about how its a great idea to use an Inspire 1 controller with the P4. I guess the Inspire's controller has greater TX power than the P4's. This sounds good and all but I'm doing the math: Phantom 4 is $1400 Inspire 1 controller is $400 $1800 for this or one could pony up an extra $200 and just get an Inspire 1. In this case why wouldn't anyone do this instead?