Smudger
As to the BA incident you describe.. I would never in a million years consider a transatlantic crossing on 3 engines on a four-engined aeroplane having had a fire warning, successfully extinguished or otherwise..
At the risk of restarting another Hamsterwheel, the BA crew you are referring to did not have a "fire warning", they had a significant engine surge which led to the engine being shutdown.
UK CAA comments here:
http://www.caa.co.uk/docs/33/factor2...on%20G-BNLG%22