So how does pure water with a tds of zero made using Unger resin do a better job than pure water with a tds of zero made by another company?
I may be wrong but isn't it the tds that is important?
Also, if you done that job just once , using unger resin, how do you know it was done quicker and better than had you done it using another companies resin.
You can't have a comparison involving just one item or one job.