General info about shockers via google seem to suggest that 50-100 k miles is normal.
Mine are OEM at 13 years old and have done 53k miles and appear to be working well. They have been supplemented by Rog’s bump stops for the past 5 years.

Doug
2011 Plus 4 in Rich Maroon

1972 750 “ComDom” sprinter
1958 Triton 650
1992 Triumph Trophy 900