I too am a DE Charter member from the Ford card.
The benefit is a maximum of $500 cash toward a car purchase or lease earned at 2% of any purchase. Max accrual is $1,500 and the cash expires after 3 years. There is no further accrual at any percentage after the $500 max per year is reached.
I use this card first to get the 2% then move to the Fidelity Cash Rebate card at 1 1/2% unlimited.
There is no other card that allows you to earn 2% on any purchase.
I don't believe the DE Charter member card is offered anymore as the rebate percentage is high. I am glad to have it and glad Citi keeps the Charter members.