Use the water as it is - no conditioners necessary. However it's not a bad idea to get a TDS meter to verify that the "product water" is 0ppm TDS or close to that. That way you know exactly what your putting in your tank without going on faith, and you can monitor when your RO/DI medias need replacement.
I have an AquaFX unit and like it very much. Good quality fittings & materials and the company offers decent tech support if you need it.