Cathay’s long haul economy is already pretty solid. Not amazing, but comfortable enough if you plan it right. For BOS to HKG, yeah it’s long, but $6k extra is a lot of hotels, food, and experiences once you land.
Premium economy is nicer for sure, more space, better recline, quieter cabin. But I don’t think it’s “$2k per person nicer,” especially with a 4yo where the kid probably won’t fully benefit from it anyway.
What I’d do instead: grab good economy seats early, aim for a bulkhead or exit row if possible, bring your own comfort stuff, and maybe splurge on one or two nicer meals or experiences in Hong Kong with the savings.
Unless you’re very tall or really struggle in economy, I don’t see premium economy being worth that jump. Business would be a different conversation, but premium economy at that price feels like bad value.
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