Does anyone use filtermag

I just saw this product in the new Performance Products Catalog and was curious about your opinions on this product or similar ones. It seems like a good idea in theory. I searched the forum but couldn't come up with a another thread that was relative to this

Is that the screen you put on your oil filter? If so they look like a cool idea.

No I was referring to this, filtermag.com, it a magnet that attaches to the outside of your filter to capture small metallic particles that are two small for the filter to capture