Guarded boy: I have (as Fantasee has mentioned) a Neosteel shemale belt, but with a wire string. I can highly recommend it. I bought the system module belt because it is retrofitable. The total module is -as I have understood it- not .
I dont know if the ergo rear module is good or not. I assume that the skin on your bottocks might get trapped when you sit down but that properly depends on your build.
I can recommend it, but remember that it takes a lot of betting used to and a lot of bending, and remember: Be very thorough with the measurements and visit Dr. Mende if its possible.