More details would be helpful, like city pairs in particular and times and equipment.

If you are flying LHR-BOS, the flight is so short where it doesn’t matter. If you’re doing LHR-SEA, it’s still a pretty short flight, but it’s an extra ~3.5 hours in the air, so changing might have some more impact.

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I sleep just fine in both. I prefer the 787 to the 767 and a330, but I also don’t want any service. Just a bed and to be left alone. I like the 787 business class setup a lot, but some hate it. Course, you might be on an virgin a330, which is why more details would be helpful.