Originally Posted by
slawecki
if you leave your luggage at the end of the car, there is a possibility of it being taken.
The ES doesn't stop between Rome and Florence so the hop on/hop off theft problem for luggage stored in the end of car area isn't really an issue for the OP.
W/that said - to the OP: unless you have been to Rome many times and never been to Florence, I wouldn't try to fit in a trip to Florence. Also, even in Winter time, 10/11 pm isn't considered late in Rome.