Had a great time in Italy last week, and just wanted to say thanks once again for the advice from the forumistas, especially Ron.
One observation I had of the Italian train system (beyond the amount of graffiti on the trains) was the difficulty accessing the trains themselves.
All the trains we used seemed to have very narrow entrances, with challenging steps (the platforms were all much lower than we'd find in the UK). If you have any mobility issues, this may be worth planning for.
Apart from that though, everything went 100% smoothly. I doubt very much it would be as easy for an Italian speaker visiting the UK to buy their tickets...