I'm brand new to this and have yet to purchase my unit. Last time I flew something was 15+ years ago in the world of RC planes -- I was never an expert or even very good at it and gave up the sport after I killed a plane or two 
I do not own GoPro but wanted to get the Hero4 Silver to use for other things as well.
The reason I'm looking at going the GoPro route is for cost savings; if I'm going to purchase GoPro anyway, it seems like a good idea to save some money.
Is there a reason NOT to get the Phantom 2 with the 3-axis gimble and use GoPro?
I also have no idea (yet) what's the difference between Zenmuse H4-3D vs. H3-3D Gimbal.
If I posted this in the wrong section, my apologies. I'm still trying to get my head wrapped up with all the different versions/options. Admins, please move is see fit.

I do not own GoPro but wanted to get the Hero4 Silver to use for other things as well.
The reason I'm looking at going the GoPro route is for cost savings; if I'm going to purchase GoPro anyway, it seems like a good idea to save some money.
Is there a reason NOT to get the Phantom 2 with the 3-axis gimble and use GoPro?
I also have no idea (yet) what's the difference between Zenmuse H4-3D vs. H3-3D Gimbal.
If I posted this in the wrong section, my apologies. I'm still trying to get my head wrapped up with all the different versions/options. Admins, please move is see fit.