Felt recoil is something that is individualized and based on more than one factor alone: Ie: weight of the rifle, shooting technique and most important in my mind is fit to the shooter.

All said sims(remingtons R3 a sims pad), pachmayer decel, etc recoilpads reduce the felt recoil noticably vs a standard recoil pad. How much depends on the above and each individual. IMO worth the investment, I can tell the difference whenshooting others without them, my main used rifles wear either sims or pachmayer decels, so theydo work. Will it allow you to now shoot a RUM just by changing the pad NO but it may help in learning how to shoot the RUM so it doesn't hurt as much!