Petop,
I can report that Virgin Prem. Econ. is perfectly fine, loads of room, quiet, good wine, edible food, I'd say it was we'll worth the extra.
I'll let you know about the return trip when it eventually happens, as I'm still stuck in San Franciso (currently at the airport waiting for a standby seat).
You might like to consider is taking your Mil. Docs. with you (if allowed).
One thing that has impressed my on this trip to the US is how they treat their servicemen and women at home, there's an announcement every 15 or so mins here at SFO that there's a USO lounge for service personnel and families, since you're coalition you may well be able to wangle your way in or to the front of some queues, well worth mentioning it.
Oh, and when you get to Vegas, go for the buffet lunch in the Mirage, you won't have to eat for the rest of the day (or the next if you pocket a few muffins).
Bon Voyage