Personally, I do not get the end-stage nostalgia for AA F...if it were going out with a blast, perhaps, but it's more of a whimper. I'd only consider AA for the return, with ability to visit CX F lounge at LHR. Chelsea is not getting the best reviews, here or elsewhere. Also, the connection on LH will be much more seamless--would prefer to avoid AA-BA contortions after an overnight flight.