“Runners are not squares.”
The Turntec Invincible was one of the only running shoes I know of that used polyurethane cushioning instead of EVA. As the ad states, polyurethane is more durable, but it doesn’t mention the fact that it is generally firmer as well.
Jerry Turner, the owner of Turntec, had some pretty good ideas for shoes, but Turntec is no more. Leave a comment!