It depends on what you value. I use my BA Chase card exclusively, because with ~$100,000 worth of spending you can get a pair of RT BA First trans-Atlantic tickets for about the price of coach.

Are those "worth" the $10,000-$20,000 fare difference? Surely not, but to me they're worth more than the ~$2,000 I'd get from the best cash back cards.

These partner cards really are marketing genius, and a great way to capture more attention, dollars & loyalty from your best customers.