So, I decided to try out the zerowater system to attempt to have something pure to dilute my usual water with to reduce/eliminate the need to descale. It does appear to work as advertised, since I am getting 0ppm tds out of the filtered water.

Unfortunately, it seems to have a plastic-y taste. I've verified by holding the filter directly over a cup that it seems to be coming from the filter itself, not the pitcher. I used the water to do a pourover, and the taste didn't seem to come through to the coffee. still, whatever is causing the taste may be harmful, so I am reluctant to use it.

Anyone else experience this? Maybe its something that will go away with use?

I've been using Zero for 7 months.
I add a splash or 2 of Santa Fe very high silica water to bring ppm up to 2 or 3 or 5 ppm (it's an art, not science ) and water seems to taste and brew just fine.
No offense, but are you sure you're not mistaking 0 ppm for plastic?
Try an A-B comparison with some other 0 ppm and add a bit of tap to see if it's potable.

Believe me, the idea that I'm crazy has occurred to me. I'm pretty sure that's not it though, because I've had DI water before. It tastes a little flat, but not plasticy.

Keep in mind that a TDS reading of zero doesn't really mean there's nothing in there. Its really a conductivity meter and certain non-ionizing contaminates (like say plastic) won't show up on the TDS reading.

I'm using it at work right now and mixing with tap water isn't an option, the water here will literally give you cancer. I've been playing with adding some various brewing salts to improve the taste, which does seem to help some.

So, the plastic taste does seem to be fading with use. I actually wonder if my office's crappy new "RO" filter was the source of the plastic taste. We used to have poland spring water here, which was great, but they ditched it in favor of a new filter. Since the output of this supposed RO filter was 200ppm I refused to use it given that the water around here is contaminated with heavy metals. So what I've been doing is taking the office RO filtered water and then running that through zero water. I've then been adding a pinch of gypsum to bring TDS up to 50-100 ppm, and the end result tastes pretty decent.

I'll eventually get another one for home, where the water quality is much better and I will be able to blend with my tap water without fear that I'm killing myself.

I'm at my sons in Brownsville tx, where they have some very s##ty tasting water, and we are using water from the RO/DI system for his reef aquarium and there is no taste what so ever in it. The meter show 16 ppm going into the DI filter from the RO and zero coming out.

It might be an obvious question Nate but did you wash the filter before using it? Running a few gallons of water through it before using it for drinking? It's a must do for any water filter.

I rinsed it off and ran a little water through it, but I didn't flush a large amount through because zero water specifically says this is not necessary.

I do think (know actually) that when my office installed their new RO filter that they did not flush it adequately. Or at all. I am beginning to blame my office filter rather than the zerowater for the plastic taste, or whatever it was that I interpreted as plastic. Things seem better now at any rate. I will be getting another one for at home, we'll see if I have different/better results.

Check out Bulk reef supplies RO systems. Great systems at a good price. They also have great filter life and doesn't cost a fortune to change. We have four installed for drinking water and aquariums. Also realize if you have below about 55 psi water pressure you really should run a boost pump for the system to function properly. The ones we are using luv about 80 - 90 psi

Followup on this since I don't want to unfairly disparage the zerowater system: I am now convinced the "plastic" character had nothing to do with the zerowater, and was in fact something going on with the water system at work. It has fortunately faded, and I've since got another zerowater pitcher for home and had no such issue with it.

SOMETHING was causing this plasticy taste though (I wasn't the only one who noted it) so a worthwhile takeaway from this is: zerowater can't remove all contaminants, and not all types of contaminants show up on a tds meter. All that aside, the zerowater system seems to work as advertised, and I'm happy with it thus far.

BTW, thanks to BenKeith for the RO recommendations. I may want to install RO at my house some day, but the system I've been complaining about was installed by my employers and not something I have any control over.