Lufthansa is rolling out beds (but not totally flat beds - they slope at an odd angle!). The LH website tells you which routes are going onto beds on what date. This would swing it for me, without a doubt.

Virgin fly to Delhi a couple of days a week, so you may also find you can get a good price SFO - LON - DEL if you go and come back on the right days. VS Premium Economy is seen as marginaly better than BA, if only because you get a separate check-in desk.