Product review (2 stars): Changed from five star to two star
Our water has taken almost two minutes to get hot and it's always really troubled me to waste all that water.  In winter, I'd also love to wash my hands using warm water.  I couldn't be happier now just to press the button, fuss around the kitchen, and a few minutes later turn on the water and have it be hot.

 A few caveats: 1) I think it probably needs to be professionally installed, because my husband is Incredibly Handy (as in rewired our whole house, for one), and it was beyond him.  So budget that in when considering the price.  2) You've supposed to install it at the farthest point from the water heater, but our powder room was the farthest and has a pedestal sink, so there's no place to install the system, so we put it under the kitchen sink.  This just means that when we turn on the water in the bathroom, it takes about 15 seconds for it to heat up the portion of pipe that goes from the kitchen to the bathroom.  Still well within reason for us.  3) Our 1,800 sq. ft. house is a single-story, which works well with this system.  If your house is larger, I'd do more research.  But for us it's been heaven-sent.

Edit:  Although we loved this product, unfortunately it stopped working after only about half a year.  For the cost, that's incredibly expensive. And now we're back to where we started.  Our bad for not following up and trying to return it/get it fixed (but should be have to spend money to get it fixed after such a short period of time?), but we were swamped during that period.