Hilton’s premium co-brand is interesting because it straight up comes with Honors Diamond status, though I view Hilton Diamond as worth less than similar status at Hyatt, Marriott, and IHG (no guaranteed late check-out from Hilton or IHG, even, but at least IHG offers confirmed suites).
The premium card is also the only one where Hilton spend is more rewarding that putting it on an alternative card.