We had the US window factory change all the windows in our house on 6-5-09, spent $4, 662. There is a lifetime warranty also. They installed the windows and left without checking if all the windows work properly. We tried locking the windows with negative results. The top part is loose and keeps coming down in ALL the windows in the whole house and the windows do not lock. My 3 yr old niece was standing with her hands on the window panel and it came down almost crushing her fingers, she was hurt. The windows are loose and often keep sliding... read full review »