i would doubt that those ralphs filters are zero tds? did you check it? drinking water is supposed to have some minerals in it for you which is why we dont drink distilled...
and although i think those machines are okay in a pinch or maybe 'just starting out', i think the op wanted zero...
i think anything better then regular unfiltered water is good, but depending on the system and the contents and all the other factors, i can totally understand why folks want zero tds... and if you ahve a filter and paid good money for it and take care of it like it is supposed to, then i can completely understand expecting zero out of that as well...
but either way, it sounds like the op is satisfied... I would like to know if it really is zero though for future reference...
thanks
s