Opinions on RO/DI systems

[christyf5]

I've got an aquasafe unit, I think I bought it in 2003 or thereabouts. Changed the RO on it for the first time last year (I don't know whether it needed it or not, but I did it anyways). I change out the filters about every 6 months or when I remember. DI probly gets changed yearly on it, although I bought one of those see through canisters that has the color changing resin so now I'll change it when it turns orange.