Thank you all for your replies, I decided to stay with BA as the price was cheaper even when I included, car parking and the need for a hotel. Late afternoon return flight suits me better too, the idea of getting up at 04:30 for a 7:00 departure didn't appeal to me, although I do appreciate the need for that slot to link at LHR for flights to the USA.
I shall try VS if I can, not merely because I would like to check out the Clubhouse at LHR, and I do hope the route is a success......the NQY-LHR route is always a busy one.