Arm strength is not the most important quality for a QB (see Ryan Leaf and Jamarcus Russell).
Command of the offense, intelligence, is close to the top. Accuracy matters more. Leadership matters. Joe Montana and Tom Brady didn't/don't have cannons.
Cardale has has grown as a leader and in accuracy, but also has a cannon. JT is a born leader, with a better command of the offense, with good accuracy, and good not great arm strength.
I feel like JT has an overall edge on Cardale...for it seems the only clear cut place he beats JT is in arm strength. That may also help the running game a little bit more too. Both a great guys. Cardale may be a better pro-QB prospect. I'm not down on Cardale. I just think JT ranks higher in more categories and will win the job.
Man, Buckeye problems... :)