On a short sector like JFK - LHR, travelling in F is hardly worthwhile/necessary....hence the debate. [Keep in mind that JFK - LHR is often less travel time than JFK - LAX.] IME, travelling in J upstairs on the BA 744 is sufficient, and generally a much better value proposition. Back to your question, imho, the current AA seat is superior to the current BA seat....but the lounge situation at LHR T5 gives the nod to BA.