maybe u wan to provide the specs of the model u comparing. I'm using zerox... should be 5stage. the ro membrane is the last stage. bear in mind if u living in hdb, n high floor, u might need a booster pump. better buy from a seller with booster pump on hand So tat u dun need to source for 1.
To me, all rodi units built all using similar housing. the filter media are the ones sort of mine is better than others... etc. etc. they all do their job.
Maybe should look into easy replacement of media n media pricing. The less u utilize the unit, the longer the media last I suppose.
So important thing is product support.