The Silverpuppy and the Silvergen are both excellent. I give the nod to the Silverpuppy for ease of use. The round electrodes on the Puppy are easier to work with. The flat electrodes on the Silvergen get bent to easily. Both have same specs and very similar design. The Silverpuppy is smaller but can produce the same amount of CS (quart jar). Both have the Current Control feature so you get very good quality CS either way.