I play at a club here in Germany, as well as at a different club when there are no courts available. The second club has a squishy green carpet that looks like grass, and seems to be slick. At this second club the ball tends to skid and come off the surface low and fast. My club has a woven thin carpet that is fast, but not quite as fast as the other club. The ball also grabs a bit more. How many kinds of indoor carpet are there? What is the degree of variance? Note that I am not including granulate faux clay in this discussion.