As Start-Stop becomes more readily available in the U.S. market, it's only logical that we'll see more and more people asking about it's efficiency and whether or not it's a solution in search of a problem. I've driven vehicles with this feature before but the Alfa is the first I've owned with the feature. Since purchasing, I've driven with the feature disabled, not because I didn't believe it worked, but because I didn't like the transition from brake pedal to accelerator. Over the past week or two I've forced myself to leave the feature engaged and try to get used to it. It's been successful so far, learning the "trigger point" so to speak has allowed me to basically decide when I want to engage the feature at a stop and when to bypass it. While this evidence is anecdotal, I've seen an instant jump in fuel efficiency of approximately 1.5mpg in my daily commute. I decided to dig into this a little and see if there was some true evidence showing a point of diminishable return with the vehicle being turned off and restarting versus letting it idle. Basically, I was looking to see how much idle time equals the amount fuel consumed in restarting the vehicle. In the old days with carbureted engines, starting a vehicle could consume a considerable amount of fuel as opposed to idling it. With todays computer inputs, the amount of fuel startup fuel is drastically decreased. While it's old (2007) this analysis is one of the most comprehensive documents I've found on the subject. While no two vehicles and driving patterns are the same, this does present some pretty good information. Enjoy the read! If you have some of your own on the topic, please be sure to share Tldr; A few seconds of idling consumes more fuel than the starting procedure of a vehicle.