Some other things to consider re: CO vs. others in coach.

Carry-on baggage - CO will let you bring on more than VS, which will allow only one item, even from the US, and will weigh that item to make sure it is under their limit, which used to be something like 14 pounds. Others may have more up to date info on the weight limit. So, a bag that other airlines would let you bring on board, VS will force you to check, which can be awkward depending on what else you have with you to use as a carry-on bag. Further, and this should change by the time you fly later in the year, when flying from the UK, you are only allowed one carryon; you don’t get to have both a carry-on small roller bag and a computer bag - you get to take one on board.

Drinks - in CO coach, you have to pay for wine, beer, hard drinks, while EU carriers don’t; I have no info on the other US carriers. Again, others may have better info on this than I.

Plane Size & Flight Time - by the time you fly, CO will be operating to Heathrow, which can be abominable, as well as Gatwick. Right now, it’s just LGW, and I’ve had to wait as long as 1 1/2 hours to clear immigration because flights from other countries have come in at the same time as the later flights. Also, the bigger planes usually get in earlier in the morning, and you will likely find your hotel unable to give you your room for several hours, as opposed to arriving later in the day. Depending on where you stay, they may have a freshen up room you can use briefly, or not. By the fall, CO is supposed to be running a daytime flight from the US to Heathrow.

Entertainment Systems - Whether you have the new AVOD system, or the old everybody’s movie starts at the same time system will depend on the plane you’re on. Given the delay in CO getting the 787’s, they are rejiggering the fleet around, so it’s hard to say now what you are likely to get in the Autumn.

Just some of the other things that will come into play.