Replying to School Movie Project

So I've been taking film classes at my college. This quarter I'm in the advanced class and for one of my projects I am filming a parkour edit with a kid in the class who is very talented with my gopro hero 4. Hopefully I am also filming a mountain bike edit for my other friend also with the gopro. I am also working on a school project and I will be using both our Black Magic Cinema camera and our 5D mk3. I might be taking the class next quarter and I have to make one big project. I am thinking about making a short mountain bike film with a couple of very talented riders my friend knows and rides with. For this caliber of film I want to use a better camera then a Gopro. Should I use the 5D or the black Magic? any advice is helpful.