This is our fourth round of Indow Windows as we gradually insulate our 1923 house as well as we can without rebuilding the windows! This time was the first time we worked with the custom fit kit instead of a person coming out to measure for our inserts, and we were worried, but the fit is excellent; the kit was very clear and easy to use. We will be back next winter for our next round! Our only problem was with TFreight, who gave us the wrong phone number to contact them for delivery, then gave us the wrong delivery window, then delivered to us without warning and tried to leave our windows out on the front sidewalk ("I don't do stairs" was the comment from the driver). Please get a new delivery service!