Originally Posted by bhomburg

That's what I usually do, too.
See that you can select seats in the minicabin at the very front in rows 3 and 4. And preorder your meal.
Really, the only downside to using AA/BA is the connection in LHR. You'll need to change terminals which means a long trek through a crowded airport, and have to pass through security which is a PITA in LHR.
You will have access to one of the the BA Galleries club lounges in Terminal 5 (there's two, North and South, select the one that's closer to your connecting flight's departure gate). Those have showers and there's food and drink.