I don't like pushing brands but in this case I have two independent verifications that the AOR brand was better. Now the one used before the AOR was a mix of Inositol & IP6 by another GMP manufacturer so there should have been NO difference with similar doses.
In theory any company with a GMP license selling pure IP6 should be OK. AOR calls for therapeutic doses of +2g but others have used less with success.
Outside of AOR I would pick NowFoods (GMP) but they add calcium and green tea to theirs:
EDIT: Removed link to this one, it contains calcium and that makes no sense to me.
vi. Challa A, Rao DR, Reddy BS.(1997), “Interactive suppression of aberrant crypt foci induced by azoxymethane in rat colon by phytic acid and green tea.” CArcinogenesis 18(10): 2023-6.