Do you mean the genuine HW one that goes over the front sight?
I do not have one if these but do have a different slip on mod on for my 99. I bought it off a member on here . It's very good.
Lots of people menion the action is the loudest part of a Springer, more than likely true. However down range the mod makes quite a bit of difference to muzzle crack
I found it out more weight up front too, which I quite liked.