I'am thinking about booking the following flights for an upcoming trip to the USA in late August:

BA 917 STR-LHR
BA 49 LHR-SEA
BA 282 LAX-LHR
BA 920 LHR-STR

The point is that BA.com quotes the flight at EUR 451+ which brings the total up to EUR 676.52. AA.com gives me the same itinerary for USD 658+ or USD 790 including taxes.

There is therefore a difference of ca. 120 USD in favor of the booking done via aa.com. Has anyone of you booked BA flights via aa.com? Since the site states that all non-AA operated flights are only on request, I really don't know what to do (i.e. am I really getting this fare confirmed by AA in a second moment or not?). Any advice/personal experience with this matter is appreciated.