Ok,
So I looked into the systems briefly:
What do you think about these 2 types for the SpectraPure RO/DI systems for my 120 gal setup?:
SpectraPure MaxCap RO/DI System, 90gpd w/ Pressure Gauge & Purity Monitor
or
SpectraPure Maxpure 90 GPD RO/DI System.
or would it be better to go bigger...