Is the 8mm non-impact roll more durable than the impact version? Will treadmills and other heavy stationary equipment cause the impact roll to compress / indent over time?

Our 8mm Strong Rubber Rolls in both the standard and the designer series would be more durable. Their main function is to protect the subfloor when dropping heavy dumbbells. Our 8mm Impact Rolls - Designer Series are made to give you the best of both worlds. They have a durable top layer great for placing fitness equipment on and a nice thick rubber underlay, giving you added shock absorption when performing high-intensity workouts.