I have the Metlund D'Mand system. I took a quick look and I believe it is also sold as the Taco D'Mand System. Here's the website where I bought it. http://www.hvacquick.com/howtos/howto.php
I installed it in 2006 and have been very happy with it. It's installed under the vanity in the master bedroom bathroom (farthest point from the hot water heater). I have a wired button on the wall (with a pilot light I added to tell when it's finished running - although you could probably just listen for the pump). I also have two wireless buttons in other bathrooms. It takes a minute or two to warm up the water, and it does mean that your cold water tap will have slightly warm water after the pump runs. My 93 year old father in law loves it. When he gets up in the middle of the night he hits the button before using the toilet and when he washes his hands he doesn't have to do it with ice cold water (we're in CT with our own well, so the cold water is very cold). Except for changing the batteries on the wireless buttons, it has been maintenance free for nearly 8 years.
Edit: It looks as if the Metlund S70, which is what I have, is no longer available.