I don't know about the McDuff guy but I was familiar with the marketocracy website. I followed it for a few yrs (3 or 4) around 2001-2004 and was not impressed with them and so I dropped them a while back. I could not verify all these claims about their performances, actually the track records of the rated 3 or 4 star stars.
Imo they are about the same with the Motley fool bunch. May be there are some stand outs but I sure couldn't tell which ones they are and it was hard to verify their claimed track records.
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