Should you only hit off the tee line turf, or is it also comfortable to hit off the center mat surrounding the strip? Also what is the cost to buy an extra tee line turf strips?

I would probably recommend only hitting off the tee line portion, more because of the thickness of the turf itself than anything else. The other turf is only about 3/8″ thick, so it will wear out much faster than the tee-line. We should be getting the extra strips this week, they will be $99.