I've flown LAX-LHR for almost 10 years now - multiple times a year. And back when I started doing that, Virgin just crushed everyone else. Nobody came close in economy. This was when the A340-600 was new and the cabins were new and everything was great. But the last few years they've become way too "Essex" - from the sugary food, to the staff, to everything. It feels like a Thomas Cook charter back there now. Upper Class is still good, but I've only done it a few times when someone else paid.
These days I fly Air New Zealand on that route. They're just a marvel of minimalism, reminding me of the heydays of SAS. Food is clean and uncluttered, not too sugary, even the tray is pressed wood and looks really cool, like a designer piece. The 777's on that route all feel new and and every seat has power outlets in economy. And the cost is the same. Hard to beat.
BA I've had very bad experiences with on this route. Why they seem to run the most ragged and old 747's on this route to the entertainment capital of the world I don't know. I hope they've improved since last time which was a disaster:
http://www.pprune.org/airlines-airpo...-carriers.html