Traditional QoS related studies handle technical KPI (key performance indicators) which are supposed to measure the quality of telecommunication services. However, while trying to select an ISP, most users are not able to choice the most suitable one for their needs. This papers presents the application of a perceived QoS based model as a tool for helping users in this kind of decisions. Our model represents the impact of each one of the objective performance indicators on the perception of quality for a particular user profile. Once the model is built common users will be able to identify the best combination of performance indicators for their pattern of use of the different Internet services. We have used velocimetro.org, a website that provides measurement services for common users, in order to feed the model with real world values and compare 4 different Spanish ISPs.