After having 7 windows installed in our house we were very impressed with the quality and appearance. Fersina manufactures and installs the windows, and stands behind the product. After the first winter, we had 1 pane with a split in it - might have been from our young son's bed being by it (he's rather rambunctious). They came out and replaced the window without question. We just had them install an eighth window, and we are still very impressed.