I used to always search first on Google flights but have found recently, that often better J fares can be found that don’t show up at all on Google- I usually check Amex travel first who has a couple of great deals lately (as much as I hate actually booking through them) and even some of my favourite airlines directly. Maybe it’s more useful for cheap Y fares, could very well be.
Especially the flexible date best fare feature I find utterly useless as the cheapest fares are usually on airlines I’m not keen to use.
