Lamp worked great for 9 months then failed. Two of the four LED "filaments" stopped glowing completely, while the other two glowed very dimly. "It's good that there's a 2-year guarantee," I thought. So I contacted TP-Link to file a claim, which consisted of answering a long list of questions, turning the lightbulb on and off 10 times, filming a video of the error and emailing it to TP-Link send, answer more questions and register the bulb and finally get an RMA number. My dull satisfaction was only temporary when I found that I had to pay for shipping my broken lamp to TP-Link before they sent me a replacement. It's not worth it when the shipping cost is close to the cost of buying a new lightbulb. To our disappointment, TP-Link won the guarantee game.