Thanks. I assume you mean that the older (2007) camera's bus is limited. I wonder if I get *any* camera benefit from the speed other than the faster download in my Lexar card reader, for which they provided a firmware update (from UDMA6).
But other messages among the participants have me wondering if this card (I have my replacement unit from Amazon) is actually a counterfeit. I plan to call Lexar and ask how to tell. The packaging, in retrospect, seemed dodgy. I have kept the packaging to work with Amazon and Lexar to resolve this.
My worries about the original CF unit (same model of "Lexar" 400x 64Gig came from Error 30 messages during a long real estate shoot with lots of LiveView requirements. First freaked out and blamed the camera, worked with a Canon tech and we began to suspect the card, and there have been NO error issues since, with some LiveView use during AFMA testing.
So, the investigation continues.