I have used several different materials on the bed of my truck/s, Linex or similar spray in liners excepted. With that experience only the horse mats have prevented or reduced the TC movement. I recently acquired a 2004.5 Ram that has a Linex spray in liner. I have known this truck for the past eight years, and it hasx never been parked under a cover. The Linex is not faded at all. The truck has carried a TC, and you cannot tell looking at the bed. Absolutely no damage to the Linex. The previous owner used nothing between the TC and Linex, but there is no indication of that fact.
Last week in the process of setting up the '04 Linex sprayed truck, I purchased 1/2" thick horse mats. Unfortunately, they are only 3'x4'. I will split them so when placed in the bed, they will be wider than the TC, so the edges of the TC will have support. I will spread then to touch the wheel wells, about 54" wide.
At this point, I am impressed with the Linex. Absolutely without flaw. My son has a Ram with a different spray in liner. It has separated in several areas and is faded. If I were to purchase a new truck, I would definitely go with the Linex liner, and horse mats.
Wayne