Jason, welcome to the boards.

If you are comparing DC to AMEX, I would suggest you look at these points:

DC is not accepted at as many places as AMEX. But, if most of your charging is Airline, Hotels and Rental Cars, you will be fine. I found that 1 out of 2 restaurants will accept DC.

DC points are IMHO much more valuable than AMEX points. DC runs double miles redemtion promos more often, AND DC points are transferable to almost ALL major airlines.

If you use the card to rent cars, the DC insurance is the Primary insurance. AMEX insurance is secondary, meaning you will be forced to use a personall policy first.

DC provides 350,000 of flight insurance vs 250,000 for AMEX.

DC provides you with 2 billing cycles to pay your bill. AMEX provides 1.

I use DC and a Chase/CO card. I got sick of AMEX "Stealing" my points due to payments that were never more than 1 or 2 days late. I have not missed my AMEX card at all.

Hope this helps you with your decision!