From my personal experience on using one with a double roller timing chain. I pulled my timing cover off after about 1200 miles on a new rebuild to swap cams and my tensioner was worn down to half the thickness on the pad, due to the chain cutting into the plastic. I think they are fine on a non roller timing chain, but the roller chains act like a saw on the plastic tensioner pads. I opted to not put it back on while swapping to my solid cam.