I suspect Cam Newton will have a similar New England experience to guys like Carl Crawford, Hanley Ramirez etc before him.
If the Pats were gonna win 12-14 games (or the equivalent), I think the Pats and their fans would tolerate a player (especially a black player) who is more of a character off the field and who isn't always the most accurate passer.
I expect the Pats to be more of a 8-9 win team, maybe 10 at best. That means an up and down season and fighting just to make the playoffs. I don't expect Pats fans to handle that well, especially with a QB who is such a contrast to Brady.
It'd be awesome if the Pats rejuvenated Cam Newton and he became the new franchise QB. Even if he just has one very good season and then leaves, that could still be good for the franchise. I hope that happens, though I doubt it.
If Cam isn't clearly an average or better starting QB and the team is up and down, I hope they let him go and give Stidham some run. The Pats won't be a relevant team again until they find a franchise QB. Assuming that's not Newton, they need to figure out if Stidham can be that. If Stidham doesn't have that kind of ceiling, the Pats need to be focused on finding that guy in the draft.