Product review (4 stars): Works really well!
While I'm not an enviro-whacko at all, this device works as advertised and eliminates the need for any detergents/softeners/bleaches, etc. which can only be good for the environment in the long run.  The 4 star rating is only because you need to tweak the blue lever under the unit every time you run a load.  If you don't, it will rarely start on its own.

We've run a lot of laundry since the unit was installed with no problems (about 2 months ago).  I'm using a top-load washer.  Everything so far has come out fresh and clean.  In fact, I really prefer it to the perfumery smell imparted by detergents and softeners.  There is a slight ozone odor when the washer is filling and during the first wash cycle.  I've never found it to be objectionable - it's a very fresh/clean smell.

One word of caution when installing the unit - be sure to connect the bottom left connector to the hot water inlet on your washer, then select something similar to "warm/warm" on the washer's temp selector.  This seems to improve the overall fill time of the washer.  (I'm on a well - my overall water pressure is less than that for those on public water systems).  Also, consider replacing your washer hoses if they are more that a few years old when you're installing this unit.  Washer hoses deteriorate over time, so this would be a great time to replace them.  Don't skimp, $20/hose for the best quality can buy you a lot of security and peace of mind.