The sense of smell is one of our most primative senses and deeply connected with our emotions. We never forget a smell! When we smell that smell, it always takes us back to when we first experienced it. The smell of a real Christmas tree, the smell of our first electric train, the movie theater, our first grade school room, and of course, the smell of castor from the exhaust of a model airplane engine.
That's why I don't get too into electrics, it's not that I hate them, they just don't smell right.