From the initial quotation, to the demonstration of the product, to the installation and clean up, everything was done very professionally. Window removal and installation was completed quickly. The reason for the four stars, as opposed to five, was that I felt there was insufficient blocking placed between the window frame and newly-installed windows. Instead, the window was screwed directly to the frame and expanding foam insulation was used to keep the window in place. Is this standard practice? I am not sure but everything I have seen indicates that shims or blocking should be used to firmly anchor the window in place. Aside from this, all was very top notch!