What the poster heard might have been my own story (posted here) about what happened when I sent MPB my Sigma Sport 150-600mm zoom in really pristine condition. They told me that there was "light moisture" internally and dropped the value significantly. This didn't smell right to me, so I asked them to return the lens. They returned it without 1) the Lenscoat, worth upward of $100, and 2) the substitute lens foot I had purchased from Joby at a price of around $80. They apparently "lost" these. Moreover, there was (and is) nothing wrong with the lens at all.
I think people need to be very wary of these companies, which is most cases get away with downgrading the value of particular items, assuming that the seller will shrug off the "small difference" in value.