The Indows are well-made, fit reasonably well (the corners are a bit off), and seem to be providing both sound and thermal insulation, as predicted. We haven't had them installed long enough to form a solid impression of their performance in both areas. The design fits perfectly with our 110 year old windows and we hardly notice the inserts at all. The packaging involved in the shipment was a bit daunting (lots of cardboard, wood, straps, etc.) and I'm not sure how we would have handled it if we had ordered more than 4 windows. Probably would have had to hire a Task Rabbit or someone similar.