I'd love to hear comments on this WATTS system:
[http://www.watts.com/pdf/Scale_Prevention_Systems.pdf]:

• pros/cons
  possible effects on taste, since calcium is not removed

Reference #1

Watts has this technology named Scale Net. This technology prevents all
the negative effects of calcium, while allowing for the positive health effects
to remain. The system is maintenance free, chemical free and salt free and
does not require regeneration or backwashing.

full article: http://www.excelwater.com/downloads/ScaleNet%20FAQ.pdf

Reference #2 - has some pricing
http://www.pwgazette.com/wattsscalenet.htm

So this system is kind of picky about the water condition that goes in-bound, guess I'll mark this as a con.

The units below are designed to operate on reasonably sediment-free water. If sediment is present, a sediment prefilter is recommended. Iron, petroleum, or hydrogen sulfide in well water must be removed by pre-treatment. The media manufacturer also cautions against use on water with an excess of 3 parts-per-million chlorine. (The media will last longer and perform better if no chlorine is present, so a carbon prefilter should be considered for city water use.)

There's been a recent post about this. It looks interesting, and the pdf you link to is very well written indeed. I don't know if the system is as good a claimed, but the chemistry they cite is for real, so people selling it are serious, not the usual water purification goofballs selling magnets and phosphate additives.

It could turn out this this is a real improvement in catalyst based softening over the old ion-exchange method. It also looks like they sell the process in the form of standard water treatment cartridges, so anyone who has a system in place can try it out.

One possible problem is monitoring. RO systems can be monitored by TDS meters, and ion exchange softeners with test strips. If this system converts ionized calcium into covalently bonded calcium, the change might show up on a TDS meter (iirc, covalently bonded molecules do not increase conductivity, while ions do -- anyone know this for sure?)

If the calcium is present as 'crystals'--covalently bonded calcium--will that change the effect on espresso extraction? Will it change the chemical interaction that makes water hardness desirable?

Rybolt wrote:So this system is kind of picky about the water condition that goes in-bound, guess I'll mark this as a con.

I think that type of inlet water requirement is typical. RO membranes are a lot more picky than that, IIRC.

another_jim wrote: One possible problem is monitoring. RO systems can be monitored by TDS meters, and ion exchange softeners with test strips. If this system converts ionized calcium into covalently bonded calcium, the change might show up on a TDS meter (iirc, covalently bonded molecules do not increase conductivity, while ions do -- anyone know this for sure?)

Jim, I am not sure of any independent tests providing that answer, but I thought of the same question after reading this excerpt (below) from reference #1 in OP.

Because the ions are formed into stable bonds, the TDS is thus lowered. Please
note that a TDS meter does not directly measure the total dissolved solids, but
rather the conductivity. It cannot distinguish between bonds and dissolved solids,
therefore it is not suitable for this system.

shadowfax wrote:If the calcium is present as 'crystals'--covalently bonded calcium--will that change the effect on espresso extraction? Will it change the chemical interaction that makes water hardness desirable?

At worst, the espresso will be like that made from RO water, slightly underextracted, with poor crema and no oils.

another_jim wrote:One possible problem is monitoring. RO systems can be monitored by TDS meters, and ion exchange softeners with test strips.

I called the company from ref#2 in OP (Pure Water Products, LLC
Box 2783, Denton, TX 76202 | (940) 382-3814) and they confirmed that:

there is not a good way to monitor the water, short of physical examination for scale buildup.

It's a pity; since it will make commercial adoption very difficult. Shouldn't affect their sales in the home market.

Is anyone with an existing water treatment system going to give it a try?

We are in the process of installing a water-softener for our home and our plumber has access to these products:
http://www.thescalesolution.com/
We have decided to stick with the usual ion-exchange/salt system, but I would be interested to know if this technology might be used for drinking water filter system. (so I can avoid getting scale in my HX machine).

It is very difficult to find information on this technology that is independent and/or peer-reviewed (ie. not promotional) on this system, so I look forward to hearing back from cafes that add one of these canisters to their existing carbon filter systems. It might be nice if the calcium/magnesium adds to the taste without the usual scale problems.

Geoff

I forwarded the information that everyone posted to our Water Chemist for a scientific response.

Both systems are from Watts. There is no NSF claims testing on this product and I don't believe there will be.

Softened water has a negative effect on espresso and drip coffee where as the beans will swell from the sodium and the water will channel not getting optimum extraction from the grind.