You are absolutely right about being able to send a defective S&W back for repair or replacement, Todd.  Still, I dislike even thinking of having to do that.
Even when they pick up the shipping tab it's still a pain in the tail to deal with when you should be out shooting it. I was greatly relieved that I didn't have any problems with mine. 

The shim I'm using for the Wolf reduced power mainspring is from the screw on cap of a 16 ounce aluminum can of Coors. The width of the shim looks about the same as the barrel/cylinder gap of the revolver.  Besides adding a bit more pre-load to the spring  it also provides a flatter purchase for the strain screw tip on the rib portion af the Wolf spring. I just checked on the shim when cleaning the revolver after Saturdays match and it's held up very well for a couple hundred rounds and some dry fire.

Scott