spectrapure 90 gpd 4 stage rodi unit

I wouldn't be afraid to use other resins. An RODI unit is pretty much just a plastic enclosure to hold all of the resins. They're basically the same no matter who you get them from.

 

Normally RO units all use the same 10" filters and membranes. The folks at thefilterguys.biz or Air Water and Ice could tell yu.

 

I haven't used Spectrapure filters since they day I changed out the original set on my Maxcap 90. Like Joel said, getting filters from quality vendors(and GIRS sponsors) will be about the same. The only caveat I have is on the membrane itself. Continue to get the brand Filmtec. Both vendors mentioned above sells them as well.

If you really wanted to get the most efficient membrane made by Filmtec, you can purchase the SpectraSelect membranes. They are hand tested and have a guaranteed rejection rate greater than 98% because the test results is written on the membrane.