From Rome, our plan is to go to Florence by train, staying for 1 night, then go to Siena by bus, staying for 2 nights and then back to Rome. What is the best way to go from Siena to Rome? It seems that the train will take about 4 hours and has a connection in Florence or Chiusi. I understand that the bus takes 3 hours from Siena back to Rome. Any suggestions which is better?