I'm sad that this isn't offered for the US market. I really see this option going beyond improving mileage.
1. A married man like myself could sit in his car (while waiting on his wife to finish shopping) and enjoy music without burning fuel or draining the battery or joining her in shopping. I could even keep the car cooled with the electric ac, or the automatic ac would turn the engine on if the car gets too hot inside.
2. On cold days, I could have the car start warming up the passenger area and melt the snow off the windshield a half hour before I plan to leave for work.... of course I would lock the car before leaving it running

(comfort access). The advantage is the car will stop the engine when it is at operating temperature and can run the defrosters. In fact, I'm planning on doing this anyhow without the start/stop feature.
3. Sometimes when I'm driving around town, I'll see someone I know and have a conversation in the parking lot while still in our cars and fail to turn off my car. I'm sure it would save a lot of fuel

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In the real world, I see this option being used beyond the red light and stop sign. That is with the assumption that engine kicks on when the battery is low. These comforts have me wondering why I didn't get a Prius.... Oh yeah, styling and fun

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