They are nice but I'm not sure about being my favourites. I'm not discerning enough to say that one brand is better than another!
I think Rococo used to be offered in BA F (at least when I first came across their shop in the King's Rd a few years ago). More info about other chocs in BA F in this fairly recent thread here:
http://www.flyertalk.com/forum/showthread.php?t=611607
Interesting to note!
Excellent thread, thank you.
^