The Red Bulls have two Supporters Shields and no MLS Cups. I would rather win MLS Cup if the Red Bulls had none of each, but even more given that the Red Bulls haven't won MLS Cup. Furthermore, this year the Supporters Shield doesn't qualify a club for the CCL. It's not like the Red Bulls have to choose one or the other. Winning the Supporters Shield means you host MLS Cup if you reach it. It's not like having an MLS game and a CCL in one week and resting players in one of the games. The Red Bulls don't have any more weeks with two games.
Good point. The Red Bulls are through the stretch from hell and can now focus on getting ready for MLS Cup.