Max Perception for Unspoiled Nodes

[Kherza]

So it's not worth it to invest in materia + food to try and get a better HQ rate?

Simple Answer: No.

1% is enough to unlock HQ on node swings. If you really want that extra 3-4% then by all means you can invest hundreds of thousands of gil on Perception materia and food. But it really isn't worth it. At lvl 50 MIN/BTN you should aim for 600GP and 340 Gathering total (you get 321 Perception from full HQ set). Any more GP and Perception than this provides very little benefit for the amount of gil that it costs.