[Jack]

Some ro/di's don't pump out as much as they say. It's kinda crap becuase unless you have the ideal/specific water parameters (which includes temp, water pressure, TDS, ect) The effluent will not be around the specified GPD. I have heard so many stories about kent 50gpd's pumping 10gpd, etc. The only thing I can see as far as being a pain is initally filling your tank, other than that I hardly doubt evap or anything like that will exeed 100gpd (even if you don't get that much per day) That's why I find buying anything more than a 50GPD unit is a waste of money.