RO/DI unit: Worth buying or garbage?

http://www.ebay.com/itm/151333213144

 

Very low end drinking water system at best. The housings are white plastic, not clear, the sediment filter is too coarse, no legitimate reef systems uses GAC carbon which only lasts a total of 300 gallons(that is 240 waste gallons and only 60 treated gallons nefore exhaustion), the RO membrane is probably either a no name clone or the Dow 100 GPD which is only 90% removal efficiency versus 96-98% for the Dow 75 GPD, the carbon block is only 5 microns when a good system uses 0.5, 0.6 or no larger than 1 micron and worst of all is the small horizontal hollow tube they call a DI with an unknown quantity of unknown DI resin versus a true vertical 20 oz refillable DI. No pressure gauge, no capillary tube flow restrictor and an unknown vendor.

Look at places like Spectrapure
http://spectrapure.com/Refurbished-90-GPD-RODI-System

Buckeye Hydro
http://www.buckeyehydro.com/premium-rodi-system/

or
PurelyH2o
http://www.purelyh2o.com/index.php?...tegory_id=65&option=com_virtuemart&Itemid=105

All are well known in the hobby with excellent reputations.