Thanks for the replies. It seems BA & VS are available at similar fares (c. £2,200 to SFO) and I wonder if anyone has any opinion on which might be better in these circumstances. I'm very familiar with the BA product, but have never flown VS, so a comparison would be very useful. The passengers are fully mobile but elderly and one blind, so ease and comfort are paramount, as will be helpful crew.

The factors which come to mind for me are: T3 v T1 in the morning; seating tips on VS; ease of talking in VS suites; ditto ease of conversion seat-bed; ease of connection to/from UA at SFO; any other advice you might have.

Not to be morbid, but it'll probably be their last major holiday, so I want to make it as special as possible for them. Thanks, all.