Aquasafe RO/DI?

[Reef-Geek]

Hi, I am about to buy a decent RO/DI unit, I have a 34 gallon tank and I usually do 5 gallon water change every 2 week. I am checking the aquasafe's website and they seem to have a pretty decent price for a 7 stage ro/di unit.
http://www.aquasafecanada.com/aquariumsystem.html

Has any one tried it? is it any good? what is the TDS reading(I am new to water chemistry,is tds the only standard for filtered water)?
The shipping is about 16 dollars to Vancouver, and their unit is on sale for 129.20(do I need to buy anything else except the unit itself?). What do you guys think?