I'd be first to jump on a deal like this one but it just doesn't work out for me. Looking to go to SFO for the weekend 23-25 March, BA Basic Economy is £410, with this offer drops to £310. Virgin on the other hand with similar flight timings, is £290 Economy Light - no bag, no seat selection - or £330 Economy Classic -, bag included, seat selection, accrues more miles and is upgradeable to Premium.