Experimental data sets related to e-voting systems are very demanding in order to improve currently deployed e-voting machines. Unfortunately, the studies of such data about the machines' security, performance and their evolution with respect to the social and technical aspects are still unsatisfactory. During the last four years we have been involved in the development, experimentation, and evaluation of an e-voting system. The system tried out in several regular elections, and also used in two small elections with legal value. Each experiment provided various sociological (e.g. citizens' opinions on the system) and technical data that are related to system's performance and behavior. In this paper, we present various technical insights and the lessons learned during the e-voting experiment. The methodology for the various experiments we have carried-out and the data sets collection process are also discussed. This helps to confirm existing data on the subject (e.g., data related to security, procedures and logistics) and, in some cases, provide novel information or, at least, shed a new perspective on some security-critical factors concerning e-voting systems.