That looks rather ambitiously priced for something that's pretty basic.
I make up something with a 4040, three DI vessels (one for filtering with charcoal pellets, two for DI) and an input filter (to get rid of any charcoal that may get through) with an inline TDS meter, a bag of resin and a bag of charcoal for a similar amount.
However, if you're prepared to pay for something to plug in and go, it's probably fine.
Vin