The water is very hard in my area and I do not like salt based water softeners. In the past, I have tried permanent magnet based de-scalers, with limited success. Since these have a static magnetic field then their effect seems to be determined by water velocity and, therefore, do not perform well when water flow is low. The EDDY, however, is based on an AC field and does not have this problem.I have had the EDDY for two months now and it has performed flawlessly. When I first received it, for example, I cleaned a small nozzle based shower head and recommissioned it. This unit had been set aside because it always clogged with calcium deposits. I also cleaned the glass shower doors and dishwasher. Now, after two months of use, none of these items show any evidence of calcium deposits. The water also seems softer when using shampoos, etc.I believe there may be several reasons for some reviewers to not have a good experience. These are all easy mistakes to make during the installation, especially if the instructions are not carefully followed. Of course, too many of us fall into that category. 1. It is very easy to make a mistake in winding the coils and, therefore, end up with opposing coils. 2. It is very easy to get the coil wires mixed up and this can have the same effect as a wrong winding 3. As stated in the instructions, this unit will not work on iron pipe, but how many homeowners know the difference and most water supply lines are iron pipe. 4. The electronics unit is best when it is located close to the coils 5. Expectations are too often tied to a water softener instead of a de-scaler and this occurs because customers often do not understand the difference 6. As stated in the manual, existing water pipes may have significant hard water build up in them from the past. If this is the case, then it will take some time for this to be descaled out by the conditioned water and this may initially delay optimum results.Lastly, I believe the price is reasonable and the unit is a good value. So far, the quality seems to be there as I have had zero problems.Update:It's now been almost 5 months since I installed the Eddy and my "rain shower" still does not show any issues with hard water deposits. This is one of the older shower heads with metal, not rubber, nozzles so deposits normally show quickly. Also, my glass shower doors stay clear with normal cleaning and my 15 year old water heater has been performing better. Additionally, my dishwasher is still clean. Obviously, there have not been any problems with the Eddy, either, so my report is all positive.