Thanks for all the answers. Sounds like it's the A380 again then. Much as I'd love to try a 787, the window issue seems a bit of a major one. Have Boeing tried to be too clever with that feature?
Yes, I'm aware of the EI/DUB route and pre-clearance. We've used it before to the East Coast, and I honestly didn't find much benefit in it. Immigration in the US seems to have improved generally (or maybe we've just been lucky) so there's no massive attraction in it for me. EI are ok, but the big factor, believe it or not, is price! Looking at the dates I've selected, BA will charge me £552 each for BHD-LHR-SFO, LAX-LHR-BHD. EI are charging 2600 euro for DUB-SFO, LAX-DUB. Three of us travelling.
We did the same route last year, and SFO immigration was only about 30 minutes. Also, LAX was very straightforward too (and I got 30 minutes at the In'n'Out as well!).
No, the main issue was 787 v A380...and it looks like the Airbus wins.
Thanks for your help!
PS. Will have a look at San Diego, San Jose and Oakland, but any other time I've looked at those, it always seems that the 'volume' routes do stack up a bit cheaper.