I think that many people and products on the QuackWatch site are actually very beneficial- this is mainly propoganda from the FDA/AMA. I also think the risk of argyria is over-stated, but it IS a risk.
BTW I used Colloidal Silver to jump-start my anti-candida program and had lots of die off, so I'm not anti- Colloidal Silver . I think in high strength, long term use you run the risk of argyria.