This work presents an empirical study on Web quality measurement. We evaluate the performance and reliability of Web as perceived by the end users located at the Wroclaw University of Technology (WUT) campus. The active measurements are performed periodically for a set of Web servers mirroring the same data and localized in different parts of the Internet. We report the results of a series of experiments performed by means of the Wing measurement infrastructure. Wing system has been developed by us for probing, visualization and performance analysis of Web site from the user perspective. It uses a real Web browser, contrary to other measurement systems that use their own browsing mechanisms. Therefore, the measurement results made by Wing are realistic. The measurements presented in this paper were performed using MS Explorer. Based on the measurements that we have analyzed so far, it is inconclusive to say that the round-trip time can be a good predictor of HTTP throughput in general....