I know there are countless other threads like this one but I just wanted to let anyone know, if you're thinking about making the leap into purifying your own water, the 90gpd unit is a perfect compromise between function and price. If you're consistently buying water from your LFS, this thing will pay for itself in a short time. It took just a few hours to be plugged up, tuned and running. I made about 10 or so gallons last night and another gallon to put in the fridge for drinking My TDS straight from the faucet was ~130, filtered from my fridge ~100 (filter needs replacing) and a perfect 0.00 out of the RO/DI. Going into the job, I had no prior knowledge of how to install or use anything like this. Instructions took 99% of the guess-work out of the equation. If I wanted an upgrade or needed another unit, I would certainly purhcase another Spectrapure unit. Thanks guys/gals! BTW, if anyone needs a TDS meter, I accidentally ordered 2....don't ask.