Leaf/Landborne Soulsand - and Purity?

[Aeyis]

So, when I tried to find out how to obtain botanist's and miner's soulsand I stumbled
across many confusing statements.

In a thread here somewhere people explained that it's enough to get to over 500,
like Purity 6/8. Others said to go for 550+, so that's 8/8, like here: http://ffxiv.consolegameswiki.com/wi...rial_Reduction

So, is it really necessary to fish for procs for the 550+ or could it be done with just 3*buffed methodical (500+)? Does it just improve the chances of getting leaf/landborne with higher purity?

Anyone out there who tested it properly?

Yes. My findings are as the other posters mention: low chance on 7/8, good chance on 8/8.
500 rarity would not be enough to hit 7/8. Im not entirely sure on the exact breaking point, but I know that 521 is 6/8 and 530 is 7/8 from the data I gathered a few weeks ago.

You will really want to get that 550+, for which unfortunately you will need to fish for procs. Its been made harder with the nerf (fix) to Impulsive.