I would compare it to hard plastic, but I'm not sure exactly what you could compare it to on the car. The closest thing would probably be the door panels. It's not slippery or grippy but something inbetween like you said.
I've had them in cars before and I love them. Put them in my mom's new Elantra and my dad's new Veloster. They may be expensive but they are super easy to clean or shake out and they protect the carpeting.