Overall, the inserts are great, but it is a tedious process. If you have a lot of large windows, the measurement process is pretty painful. I wish they would partner with TaskRabbit or someone to have local certified folks to help measure and install. Customer service is excellent and very responsive though! The inserts themselves arrived in great condition and all fit perfectly, which is pretty amazing since I had 6 large windows. Soundproofing was about as I had expected. Excellent for higher frequencies, not so much for lower frequencies. The window corners do not insert quite right, but I was able to workaround that issue. Overall though, the windows are doing their job and helping us and our baby get some sleep in a noisy neighborhood!!