My short answer is that SCS isn't helping PN at all.

I got the SCS last year for CRPS in my right arm. I was mostly pain free for 7 months. Then I started getting pain also in my right arm, but different a pain, which I now know to be SFPN. The PN pain isn't as bad as the CRPS pain, but it's more pervasive (both hands and feet, whereas I only have CRPS in one arm).

I tried adjusting the programs, got new ones, tweaked this and that but the SCS isn't covering the PN pain. I have no explanation for why it doesn't work. I even thought that maybe the impulses were causing the PN pain, so I shut it off. That was a really bad move that I won't do again anytime soon.

I hope others weigh in and have different experiences. Best of luck to you.