LOVE mine. Can't imagine going back to the life without it. I borrowed one from my chiropractor before I bought mine. My chiropractor is super sweet, let me use it for 6 months. Just used mine right before this post.
I have a TENS unit that my Pain doctor gave me, I use it but, the being pain free is short lived. I guess it would depend on where your pain is and how severe it really is as to weather it will work for you.