Wonderful! I loved it! I was able to drive over eight hundred miles without feeling the ache.
...I was skeptical that it would really work for me...I thought I would have to take several breaks to deal with the muscle spams that happen in my back all the time... I did not get sore or tired after the 4 hour trip and for me that was awesome. If you have to sit for long periods of time I would highly suggest looking into getting one.