As explained below, the main advantage of being resident in Italy is that registration tax to be pais on completion is lower.
Since 1st January 2007, the permesso di soggiorno no longer applies to European Union nationals living in Italy. However, British nationals must take out a residence certificate at the Ufficio Anagrafe. After having submitted the application, the local Polizia Municipale will come and check where you live, so it may take some time before the certificate is ready.
The day you are resident in Italy, you have the same rights as an Italian to the National Health Service. Pensioners from EU countries will need form E121, while EU nationals transferred to Italy by their home country will need forms E101 and E111. E300 is used for anything regarding unemployment benefits.
From: The Italian Magazine – December 2007