I've owned 4 RO/DI units. For MOST uses, the cheapo ones are just fine. However...
For a GOOD reef setup, this is NOT a place to be penny wise and pound foolish.
I LOVE my Buckeye unit, and Russ is just plain awesome for support. I've thrown 2 units away - one was from a low-end, but well known supplier to reefers (Coralife), and another from fleabay. In good conscience, I wouldn't even GIVE them away.
Do yourself a favor. Buy a Buckeye unit.
Bill
215g FOWLR... and anemones, GSP, gorgonians... carp, that isn't FO!
"I killed my first SW Fish in 1971..."