Hello all ,Do you drive a kia soul and if you do how well does it do on the highway, I have a45 min ride each way to work and back and was wondering how bouncy or how stiff or how jerky they are once you get used to it being a new car, i think they are really kool looking ,but i tend to have back flare ups and if it is to bumpy or hard hitting,or jarring it will have to be off my list, also how is the mpg on these thanks for your input