Because the Silver Bullet generator uses higher voltage generaor (48V) and makes a silver solution that is superior to what most of the higher dollar generators make. It was designed and built by the same person who has decades of experience with high voltage geneartors and true colloidal silver production who designed and built the equipment that produces the superior Advanced Colloidal Silver
As one member of my Yahoo group reported (paraphrased). "I owned a SilverGen and bought a Silver Bullet and found that the Silve Bullet produced better results; however, Advanced Colloidal Silver produced the best results of all."
I wish that the Silver Bullet had an automatic stirrer. Perhaps someday it will - although that and the lack of a fancy clamshell cover is how they keep the price so low. But in my opinion and the opinion of others it produces a better product with somewhat higher colloidal content. To me, it is well worth the extra time. Maybe some day they will offer a deluxe model or perhaps an automatic stirrer accessory. Until the do, it will remain my choice for home generators costing less than $300.
I realize that there are those who will argue that the ionic silver you can make at home is just as good as the best colloidal sivler products, including the true colloidal silver products, but they are wrong. How else to explain how a CureZone member a few years ago ran a comparison test with a home generator, a popular commercial product and Utopia Silver to see which one would prevent damp bread from getting mold. The slice of bread sprayed with the homemade solution grew moldy in just a couple of days and the slicke sprayed with the commercial ionic silver that called itself colloidal silver grew moldy shortly thereafter. Two weeks later and the slice sprayed with Advanced Colloidal Silver still had no mold.
I will note, as always, that I am not saying that home made silver from other generators or other silver solution products don't work. Just about all of them work. Some work better than other, imo, and I know which ones I vote for.