No problem Chris. Just be aware that most used RO/DI systems would require you to replace the filters when you set it up. If the membrane along with the prefilters and resin need replacing you'll wind up spending another $55-$70 on top of the cost of the used filter.
I am not sure why my input was deleted. I shared the experience I had with an aquarium supply company. Feedback is an important part of thiss community. It doesn't matter good or bad. Everyones feedback is important. If you have had a diffrent experience then you should share it. It is important that people hear as many reviews as possible. Throwing a hissy fit amd telling people they are blind and clueless is a form of intimadation which is ment to taint reviews to create a bais for you friend who works at the company. This is not right for the memebers of this fourm who are trying to get an honest opinion.
Check out ebay or Amazon. Somebody started a thread about cheap resin they got.