Yep...they're big cities and expect the same as you would in any other big city. People are the same everywhere--both the good and the bad. We got ripped off once with cab change. I'd left the cab to get the bags and DH was jet lagged. We chalked it up to our initiation fee.

When you carry the camera, make sure it is slung over you so it can't be snatched from a scooter--keep it on the side away from the road. Store your money and passport in a money belt.

In Rome, consider renting a bomber bike and riding down the Appian Way. There are places to rent at the city-end of the park. Not fast riding, but a way to be able to see a healthy length of it.

If you're into things archaelogical, a train trip from Sorrento to Pompeii or Herculaneum is a great day trip. There is some nice walking out of Sorrento, down the coast. We were in Sorrento in January a few years back. Off season, but still busy. I wouldn't want to think about riding those roads on a bike in season. Last year's Giro riders weren't happy on the penninsula either. They had the road closed for them, but it twists and turns with a cliff down on one side and a cliff up on the other.

Buon viaggio!