Well it SHOULD be Mac Jones as Cam Newton has always and will always be overrated and nothing more than mediocre, but we all know Cam Newton will be the initial starter
I think Cam will start the game on at least the first series and if he does OK will continue until he makes a couple of bad throws or reads, then Mac will be brought in. From then on it may be a duel QB job until in one of them out plays the other. I believe that would be Mac.
Cam will get the nod but will be on a very short leash as Mac has proven he is capable.
Cam will get first chance, just because of his experience. Mac will get a chance later in the season, and may never relinquish the reins once given his opporunity.