If you really believe they are all the same you are mistaken. I have owned 6 RO/DI systems including some you mentioned and there really is a difference. When I switched from a AWI Typhoon III to a Spectrapure system my DI consumption went from 150 measured gallons to 830 measured gallons on the very first cartridge. Huge difference and huge cost savings. No other vendor specially treats all of their RO membranes proven to improve their performance and then eithe batch tests them or individually hand tests them and guarantees their perfomance in writing. No other vendor specially blends all their own DI resins in house based on thousands of real world and bench testing hours and only a few use absolute or near absolute low micron filters and provide capillary tube flow restrictors. Those all add up to a much lower cost of ownership and longer component life with true 18.2 megaohm resistivity pure water. No gadgets or gimmics, just a better thought out system using only the best components and 30 years experience doing so.
