I've had one of these for about a year now -- in fact the picture in the first post is of my toilet!
Works very well -- no problems. Ours cost $200, but I noticed last time I went to Costco the price was $169 -- we may get another one or two for the other bathrooms.
We find that the low setting of the 2 flush settings works fine for all situation -- we never use the high flush at all. It flushes better on the 1.1 gallon flush than our old toilet did on the 1.6 gallon flush.
It was easy even for a non-pro like me to install.
Full story here: http://www.builditsolar.com/Projects...urDualFlus.htm
My only concern is getting replacement parts as WaterRidge does not seem to have any web presence?