which ro di filter do you guys recommend from ebay?

I got my ro/di filter from www.airwaterice.com. The cost over the ebay merchants was not excessive, for what I felt at the time to be a much higher quality system. Plus, they seemed more trustworty should any issues have come up. I just connect mine to the tap as needed but it seems that there are numerous connection possibilities. My filter that I got from them took my water from 200ppm to 0ppm right out of the box.

Also when you are calculating costs, make sure to include the cost of tester, connection hardware, etc.. different places include it or charge separate, etc..

I used http://www.thefilterguys.biz/index.htm for my first Ro/DI unit because I didnt have a lot of experience with them and wanted something that I felt mroe comfortable with customer service and warranty info, unit works great, was priced great and you can buy a faucet adapter so the unit can just hook onto your sink and you dont have to deal with all the plumbing concerns

I bought the unit from filter direct. It had 0 tds from the get go, but I traded out the DI section for the one from the filterguyz because it lasts longer and I don't have to mess directly with the resin. Since then however with the customer service of the filter guyz I will only be conducting business with them from this point.

i got the typhoon iii from them.. it seems like most people use airwaterice or filterguys..