I just bought a 2017 Energi with the Stop and Go. It does fully stop the car and start back up but if you are sitting for more then a few seconds you just have to tap the gas to get going again. I drove 37 miles like that today. Set the cruise at 60 and just steered only. Was pretty amazing but scary I will admit! I traded in a 2015 SHO that didnt have stuff this car has. Its pretty neat! Oh and averaged 78.2 mpg with a full charge during that drive!!!!!