There is a good reason that many people use Sovereign Silver - and that is that they have the best outside sales force in the business and thus get their products into more supplement and other type retail outlets. Not saying it doesn't work, but lab tests have found that it ranks among the least effective of all the products when measured by particle size and total surface area per given PPM.
Here is an abbreviated chart comparing some popular brands as well as homemade silver. Purest Colloids had even more impressive numbers.