Anyone tried the Cefaly, gammaCore, or Nerivio device?

I've seen some posts from a few years ago where people discussed their experiences. I'm curious if anyone has recently tried these, and if so, what has your experience been? What type of relief are you seeing?

I've discussed these with my doctor, but the price is so high, I'm not willing to try it without some sort of proof they work by other migraine sufferers? Has anyone had success with these devices and if so, what are you doing to help with cost?

Any tips, tricks, or insight you can share is greatly appreciated!!