Mebrane has a rejection of 90% that means it passes 10 % of the impurities which in turn will exaust the DI resin very very quickly.
A 75 gal Filmtec membrane has 98 to 99% rejection so DI cartridges will last 5 to 10 times longer.
Horizontal small DI cartridge is prone to channeling. Vertical 10" DI cartridges are preferred for our application.
GAC polishing filter does nothing for theaquarium water.
5 micron filter will not prevent the 1 micron carbon block to get plugged shortening it's life
Transparent filter housing is preferred to be able to see the media and retained dirt, helps to ID when to change sediment filter.
Output water purity should give no detectable TDS for other impurities like Nitrates, phosphates or silicates to be within acceptable ranges, the one advertized for this unit of 1 to 3 ppm TDS will only last for about 50 to 100 gallons as is, after that the DI will exaust and the output will increase to 30 ppm.
Finally service from these company seems sketchy.
You will be a lot better off spending in a good reliable unit.
Look at
www.filterguys.biz www.spectrapure.com or
www.buckeyesupply.com