Great concept and works pretty well. The auto-on feature (when you turn on the water) is a nice feature, and with the battery (see notes below) it continues to work after you turn off the shower.As per other reviews, I find that when you initially turn on the unit for each shower it will de-tune slowly after about 2-3 minutes, I just flick it up a station and then down a station and it holds steady until I turn it off. Additionally the rechargeable battery either doesn't charge or needs to be properly charged to begin with, without it you lose all settings when you turn it off/stop the water. I currently just use a standard AAA battery until I can try charging the supplied battery properly.