The timer function works great, it's really bright and puts off the perfect amount of heat. The light is just a tiny bit brighter when plugged in. I have mine set for 6 hours and use the blue and violet lights.
This planter is well worth the money. It usually takes radishes a full month to harvest outside. This is the cutest little aerogarden seed pod sized life support carrier.
Easy to install with supplied clips and screws. Comes with all the attachments you need. There are jumper cords to connect fixtures so that only 4 power source cords would be needed.