I never thought that I needed summer air for my tires, but it makes sense! I don't drive with my winter tires in the summer, do I? I've noticed far fewer fluctuations in tire pressure now that I'm using the right air. And the fresh scent is a nice touch! Smells like fresh flowers and pine needles. Reminds me of the Pennsylvania woods without the nasty ticks. I could smell my tires for days.