Liz,
  I'm relativly new at making CS but I got my generator from Silver Gen. and am 
well pleased with it. I've had it a month and have made probably 50 qts. so far 
ranging from 5 to 19 ppm. Every batch has turned out perfect. I think that it 
is important that you can set the strength and have it turn off automatically.
                                                  Bob Smith