Request to the OP, would you mind updating the thread title to something like "up and coming receivers: Q and Jamo" or something? otherwise this will get moved to assistant coach but imo this is a really good topic. To the question specifically, I think I would lean Q just because he has a better path to being the 1 for his team. ARSB isn't going anywhere for awhile for Jamo. But can't go wrong with either for next year and beyond imo.
I posted somewhere right before the season started that Q was not ready for the NFL and I had pushed him way down on my draft board, but he looks legit, skill wise.
I don't have either player but contemplated picking up both for the long term at some point. They're like the same player to me, both have really good raw talent but not enough football skills yet. both teams and their fans are talking these guys up and this past week very clearly Q Johnston was getting a lot of looks where he can catch and just go, highlighting his athleticism. Not enough of a history yet with Jamo for me to say if he's better or worse, but he's also slated to be and will get the opportunity to be the guy.
Other guys in their respective teams, not related to this specific topic, are Wilson for AZ and Mims for DEN. I would have put Mingo here at the start of the season but I don't think he's worth the same capital as these others.