I run the buffer since one came installed in my 9mm TSO made in the summer of 2017. I was, however, surprised to see it. My 9mm TS did not come with one. I thought I would see how the TSO shot with the buffer and watch it for signs of wear. It seems to be doing fine. Got spare buffers, as well, so I thought I would use it. Softens the recoil a tad, and helps decrease slide wear, I hear. I've never shot the TSO without it.