I've got about 20k between my TSO's and I'm still running the stock slide stop pins. I have backup pins and I may implement the practice and comp swap as I don't really want a failure during a match.
For what its worth, I run a 16lb main and buffers with my 40 cal TSO variants. I keep them oil/greased to prevent corrosion induced flaws.
Cheers,
Toby