Both Malaysian carriers, pretty interesting! Not that AirAsia X can tempt me - the article says that the quiet zone is in the economy class. I'd rather be in business/first class with screaming kids, although preferably just quiet kids (and quiet adults).

The last long haul exposure to a young child very nearby was in F and I praised her father for his wonderful, well-behaved, quiet daughter. I am happy to have a child nearby like that any time.