I own the TENS 3000 and 7000 models, and they work pretty well, but I believe the battery only power option makes them less consistent and smooth in the application of the stimulation. So far, I have not used the Twin Stim with batteries, nor am I likely to do so. Really nice results, and a much smoother application of impulses through the electrodes. Pain events are far fewer and the overall effect is much better than the other two units. This unit is better than most of the chiropractors had that I have patronized. Purchasing the product from Overstock yielded a lower price point than the other sources I shopped. Overall, a very good purchase. Now if it only lasts a good long time.
I received this unit yesterday. I'm still learning how to trying properly 'trying to figure it out but used I it twice for 20 minutes each time. I found it to be of a little help. However, I am certain that once I learn all the functions it will help me. If it works as well as I've been told they do I wiil be happy to reccommend it to others.