Make sure all the cameras are EX-1 cameras and not a mixture of EX-1R and ex-1 cameras. The latest firmware is different. The ex-1R cameras will more than likely work with the large cards if the firmware is up to date.
I would check each camera with the card that you are going to use on the shoot and to see if the camera will read and write to that particular card.
I had my PMW 320 which uses the same card as the EX cameras to go down when it switched slots to a large card because of the firmware update was not current. One other thing, (just to be sure that the cards have reliability) I would make sure that they are all the “pro” cards rather than a mixture of SXS-1 the SXS pro cards.
Best option is the look at the firmware versions of each camera and call Sony service in NJ.
Hope this helps.
Ronnie
Ronnie Martin
Kato Video Productions
ronnievideo@aol.com