Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Not Impressed

Looks good on paper, but the units really don't work well. I purchased two, and the difference in the car's temperature not much. The fams turn only in the brightest of light when the car is oriented 90 degrees sideways to the sun, which is not always possible. The cases flex when the window closes so the fan won't turn, so fooling around with them to get them just right takes time, then water can leak in if you get a thunderstorm because the fit isn't tight.