DI add-on ok with a ge water filter? for reef water?

well I basically wanted to know what this ge smartwater is doing in terms of removal of crap out of water. but its looking like I should just bite the bullet and get at least a 75g ro or ro/di unit and plumb it behind the ge smartwater unit. and be done with it. Ive only bought RO since last week. and needed some today. but my LFS is closed on monday, and I can see this being a hassle to drive jugs around to get water all the time..

 

If it was me i would just get an ro/di and "be done with it". There are a lot to choose from bulk reef supply,spectrapure,air water ice etc.
I use a brs 75gpd ro/di and have no complaints works like a champ.