The R/O and DI do not remove bacteria, your activated charcoal filter makes a good fist of that, but you do need to make sure that when you change over your pre filters everything is hygenically clean and not contanimated in any way...sterile.
The R/O water should be absolutely fine to drink, but keep your greasy fingers off the filters when you change them!!
The DI resin is poisonous (so I'm told) but of course you are not actually eating the stuff are you?
Water may be passing through it, but I'm not sure that actually makes any difference to the quality of the water so far as drinking the stuff is concerned.
I would love to see what a true chemical analysis of the water after it has passed into the holding containers....well, maybe not the analysis itself but rather the
result of the analysis
It's fine for tea and coffee though.
Regards,
Ian