For those considering investing in a silver solution generator, here are some characteristics to look for:
1) electrode size - the larger diameter sizes will have larger surface area and greater longevity in use.
2) stirring and stirring method - stirring is essential to produce a more uniform solution. The methods available are bubbling, magnetic stirring and mechanical stirring. To avoid contamination of your solution by airborne substances, the magnetic or mechanical stirring methods are preferable to bubbling, unless the bubbler has a means of filtering the air before it enters the solution.
3) Open or closed reaction vessel - the better option would be to have the solution vessel closed so as to eliminate airborne contamination during the production process.
4) Automatic shutoff option - this is important if you are producing your solutions unattended. The two methods are timer-based and electronic monitoring of solution status. Ideally, the circuitry should shut off the generator once the solution reaches the required concentration.
These are suggestions to guide your research into the available generators.