Used 330 Gallon IBC's for fermenting?

[kckadi]

^{I'm looking at using some used 330 gallon 'food grade' IBC's for fermenting. A local seller has used ones from a soda factory that had food grade phosphoric acid in them. The IBC's have been triple rinse and appear very clean. Has anyone had experience using used IBC's? Has anyone had issues during fermentation caused by prior contents, regardless of how thoroughly they may of been cleaned? I don't think there will be an issue but want to ask the question.}