Not sure if this is a good deal or not, but the first time I have seen non-stop flights from London to LAX at the 300 Mark from United and American in a while.
Here is a sample link
https://www.google.com/flights#flt=/...171*.GBP.35181
That comes out at 352 now, but you can price them up to 297 is using Lufthansa or Swiss.
Prices up around 320 on AA & BA
Hope it helps.