In general I have found BA flights transatlantic flights to be far easier to book than AA and cheaper.
BUSINESS CLASS 80K for BA vs 90K for AA.
FIRST CLASS 100K for BA vs 125K for AA.

So I have started to move lots of AA miles to BA and frankly have found there service to be a lot nicer, though of course I am a fan of AA in general.

The melt which I referrenced meant that usually when you convert miles, you get fewer to the other airline due to the ratios most programs use. This promotion has not melt so to speak and the miles you get are arguably more usuable for lower costs and a better product.