I like VS's Premium Economy.

You have lounge access, which provides for good food at many airports, and the seats are quite comfortable. I have flown Upper Class a number of times, and while they are really great, for the fare difference, I find VS Premium Economy my favourite.

I fly the route fairly often, and try and stick with VS as often as possible.

UA's Econ Plus is pretty nice as well for the cost difference, but overall , I try and stick with VS for Long Haul to/from LHR