This company advertised a product lower than other sites. Required a call back after submitting purchase. I was told that the lens "has a plastic fitting and will not permit auto-focus with Canon EOS cameras. I should get the $100 more expensive Sigma lens. It isn't listed on the Sigma website, because we are exclusive wholesalers for Sigma, and this lens has yet to be officially released in the US." I called back after first agreeing to this, because it seemed to me that the lens being sold is a $200 retail lens. He reiterated what he had said, then tried to intimidate by saying the credit card company will not withhold payment if I haven't listened to him. I then called both Sigma and Canon at their customer service numbers -- the Canon rep told me the lenses are not manufactured with anything but the magnesium fittings, and the Sigma rep told me that there is no such thing as an exclusive wholesaler, advance release of lenses, nor is there an authorized promotion of the lens he attempted to sell. I called the company, and they said they would cancel any charges.