If you have used E-Gate entry at Leonardo da Vinci International Airport please offer your experience(s). Sounds like it is a great process if it works.
Did it a few weeks ago at FCO. Maybe 5-10 minutes. So easy. We used the Mobile Passport app for re-entry to the US and that saved time as well.
Very quick and efficient the 2 occasions I've used it. During busy times, airport staff are there to assist and keep lines moving. You'll need to stop right afterwards and have your passport stamped, but that went quickly too.