I bought an Eye-Fi ProX2 SD card the other day. I also ordered a CF card adapter for the thing. I put the card into the camera and was bluntly told that my camera could not format the card. WTF !!! 
It seems adapters don't work with Eye-Fi SD cards
although all the sales crap will let you think it will. So forget about WiFi-ing your 5d Mkii on the cheap
I so hate CF cards, they are just lumpy old siht that has had it's day. I'm depressed
Canon, move on!
Snaps
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