I have flown BA SFO-Europe almost exclusively for over 20 years. Overall the service is excellent, they rarely cancel fights, and the food and beverages (including alcohol) is complimentary. Movie selection is fair (Virgin has much better entertainment).
However, BA charges a pretty penny to assign your seats more than 24 hours in advance so bear that in mind when add up the cost. First checked bag per person is free, second is $100 I think. You can carry on one bag (up to 22'') and a personal item free.