Have just flown Manchester - Tampa - Manchester with AA. The aircraft was a Boeing 757 , very old ,grubby and VERY cramped. No seat back TV, couldn't be seen from the window seat. We could reserve seats online and we got those seats. We flew via Chicago O'Hare ,landing at terminal 5. 2 HOURS (yes 2 hours !) spent in immigration hall. They divided passengers into 2 groups - American and Visitors. 7 immigration officers to handle approx. 130 american passengers. 3 immigration officers to handle approx. 250 (and growing) visitors. After an hour and a half some clever immigration officer realised there was a problem and found some more officers.We were already an hour late leaving Manchester and the immigration delay meant that we could not take up the AA Admirals Lounge rest we had booked and paid for. Baggage and security were much more efficient. Flew back from Tampa with AA but operated by BA. New Boeing 777, clean ,comfortable , a whole different experience. If you like roughing it on a old ,uncomfortable aircraft ,fly AA. If you prefer a clean,spacious, comfortable flight from an efficient airport (Tampa) to another efficient airport (Gatwick !) fly with British Airways ,even if my diabetic meal was disgusting. Both cabin crews ,by the way, were excellent.