I'm probably a sucker for just redeeming through the AMEX travel site. At least that way I don't have to contend with limited seat availability and still earn Delta MQMs on my flight. I don't care for booking hotel stays through third party sites like AMEX since I seldom get any elite night/points credit. I almost had 100K Hilton Honors points expire not realizing an AMEX-booked stay wasn't recognized as a qualifying stay.