I’ve recently purchased a 120 year old Victorian home. It’s wonderful, but the electricity bill was a killer. The road noice was too much, also. We bought the acoustic grade inserts. I was worried because my windows are no longer square, and I was responsible for the measurements. The service was great. The assurance from their ‘true fit’ guarantee also helped. The inserts came in last month. Instillation wasn’t that hard and the difference was instant. Our home is quiet. The AC doesn’t have to run all day every day. My electric Bill in april of late year was 600$... this month it was 350$. I’m very happy with this product.