I too was debating about whether to get a DC card....the ticket discount isn't huge and I usually ignored the rental car discounts thinking I could get that elsewhere, but the rental car discount is what really saved the most money this past trip. Via this board, I got a Dollar mini-van reservation for a weekly rate of $209. I received my DC card a week before my trip. That night, just for the heck of it I checked National car rental prices again using my Emerald Aisle Corporate account number, and got a rate of $219/week. I then tried the DC rate, and I got a base rate of $219 minus a $61 discount! The quoted DC savings says it's 10% but I always assumed that was off of rack rate....in actuality, I got 20% off of the corporate rate. The DC cost me $30 (through a corporate program), so I got a 200% return with just the rental car discount. Just wanted to mention this because I think there are other people like me who assume the car discount wouldn't add up to much, but it does.