Arch has potential. Ewers looked far better to me in games and in stats/boxscore He was a 7th round pick.
Arch should stay in school at least another year.
Sarkisian is going to play the QB who gives his team the best chance to win. Manning served as backup for 2 years to a player who would be selected in the 7th round. That tells you all you need to know. And Manning has a rather pedestrian completion % of 62% when many of his passes are dump passes. Rarely does he throw downfield.