IMO, just another way to get your money.
Most of the time, if the recoil spring is changed at a regular interval, such a thing as the "shock buffer" is not needed.
I've seen where some have relied on the shock buffer and had it come apart in competition, locking up the handgun.
"A well regulated Militia, being necessary to the security of a free State, the right of the people to keep and bear Arms, shall not be infringed."
Life Member NRA
Life Member NAHC
Former President of the ECPT (Eifel Combat Pistol Team)