That's a lot cheaper than the Rebuilder. Have you used it for nerve pain? Have you tried it with an Epsom salt divided foot bath?
The wave form is similar to the 4 lead unit my physical therapist used for extreme muscle spasms and pain caused by a herniated cervical disk, and for piriformis syndrome. That was extremely effective and soothing. He used 4 leads for my shoulder, and 2 for the piriformis pain, one on each end.
I would guess that interferential therapy would be equally soothing and healing for nerve pain. One thing that struck me going through some of the research on electrotherapy is that many different forms of electrotherapy promoted healing and reduced pain. I'm not at all convinced that the Rebuilder 7.83 Hz. pulse works better than TENS, EMS, or interferential stimulation. Again, I can recommend the Rebuilder based on experience, but realize that other units may work as well or better. It may be worthwhile to do a separate thread on electrotherapy to see what has been helping people.
For people with access to medical journals, here's a list of recent studies:
http://www.electrotherapy.org/recentrefs.htm