I'm Washington based so I only have experience with IAD but have had great experiences each time. Yes, Dulles is a bit harder to reach via public transportation but its a nice airport all in. I've never found the lounge or First dining room to be crowded. It was just redone recently and looks very nice. As others have noted the 216 is an A380 flight which is particularly nice in F. One possible consideration is that the flight time from IAD is slightly longer so if you are interested in taking advantage of F its a great choice.