Hi Mark

Here are just a few reviews other than the blog link I sent before.  Also the system as I understand it works on the quantity of water passing through so it would be installed after the water leaves the cisterna and as it enters the house. This means if you are not there it is not used but will start working again when you return and you use the water so there is not a problem if you only spend part of the year here.

http://www.motorhomefacts.com/ftopic-82329-10.html
http://www.productreview.com.au/showitem.php?item_id=57273
http://bestbuyledhdtv.techcalendars.net/seagull-iv-x-1f-ca-drinking-water-filter/#more-191
http://www.waterfiltercomparisons.com.au/

Here is the information about reverse osmosis and what I called dead water where the water is tripped of all natural minerals therefore removing all the goodness our body needs:

Reverse Osmosis Water Filtration Systems
This is a process that exposes water under pressure to a semi permeable membrane with a very fine pore structure. Because most inorganic contaminants have a larger molecular size than water, the membrane rejects certain contaminants, minerals and a large part of the water. The portion of water that passes through the membrane is stripped of inorganic compounds and trace minerals. Because many synthetic chemicals, such as herbicides and pesticides are smaller, molecularly, than water, a reverse osmosis system must also be used in conjunction with a carbon filter. Reverse osmosis systems require adequate water pressure and extensive maintenance. Because most point-of-use reverse osmosis systems produce less than 1 gallon per hour, they require a diaphragm storage tank. Reverse osmosis typically wastes 2 to 3 gallons of water for every gallon it produces and costs 18 to 24 cents per gallon. Often these products are marketed by using a demonstration that measures the TDS (total dissolved solids), and implies that this measurement shows the systems effectiveness at removing contaminants. TDS meters measure the dissolved minerals in water, primarily calcium and magnesium, and have little or nothing to do with contaminant levels or water purity. On a more scientific level, there are several credible research reports and books that stress the more recent opinion that long term consumption of de-mineralized water can in fact be dangerous. Two very negative things happen when we consume water that has been stripped of its natural minerals. First, because de-mineralized water contains more hydrogen it is an acid, with a pH below seven. Any time we consume an acid substance, our body will pull minerals from our teeth and bones to produce bicarbonate in order to neutralize the acid. Second, it has been proven that when our body fluids become more acid than alkaline the production of free radicals increases, causing increased cancer risks.

Pip