I used to work in water purification, and depending on the amount of total dissolved solids in the distillate or deionized product, there is no difference between distilled water and deionized water, with the exception of the process (small but noticeable differences would be volatile organic chemicals remaining in distilled water if it's not pre-treated with carbon, and amines in the deionized water, which again can be removed with carbon post filtration, and the deionized water will usually have more dissolved oxygen in it, depending again on post-treatment). All ultra-pure water is more aggressive than standard tap water until it reaches a certain equilibrium of dissolved solids (they don't call it the universal solvent for no good reason). So if distilled water with a conductivity of 25 mmhos (micromhos) or less is going to be reactive, then the deionized water of the same conductivity will be just as reactive.
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I used to work in water purification, and depending on the amount of total dissolved solids in the distillate or deionized product, there is no difference between distilled water and deionized water, with the exception of the process (small but noticeable differences would be volatile organic chemicals remaining in distilled water if it's not pre-treated with carbon, and amines in the deionized water, which again can be removed with carbon post filtration, and the deionized water will usually have more dissolved oxygen in it, depending again on post-treatment). All ultra-pure water is more aggressive than standard tap water until it reaches a certain equilibrium of dissolved solids (they don't call it the universal solvent for no good reason). So if distilled water with a conductivity of 25 mmhos (micromhos) or less is going to be reactive, then the deionized water of the same conductivity will be just as reactive.