Sandisk Extreme Pro 64gb - exfat or Fat32 - That is the Question...

[NickZee]

Sandisk Extreme Pro 64gb SDXC can only be formatted to exfat in Windows and the t3i also formats it as exfat.  However, the EOScard CHDK Wiki says that it must be FAT32 of FAT16.

Magic Lantern Install instructions tell me to format in Camera but should I use a tool like fat32format to achieve FAT32 and not format in camera? Ever? Because every time I format in the camera it converts it back to exfat.

I've been using Magic Lantern for about a year now.  Only after I got this 64gb card, every now and then, the card will become un-readable (in camera).  One minute it's working great, then I turn off the camera, wait for red light to stop blinking (could be seconds, or several minutes) then turn it back on and the camera will say it the card needs to be formatted.   It happens randomly (sometimes days and several thousand images between corruption), and with out warning.   The only constant I can pinpoint is that it happens in the camera when powering off and then back on.   

I usual use ML Nightly Build (magiclantern-Nightly)

My original question about exfat or FAT32 is an attempt to diagnose why the card becomes corrupt in camera.

Thanks in advance!

Links:
http://www.sandisk.com/products/memory-cards/sd/extremepro-sdxc-sdhc-uhs-1-95mbs/
http://chdk.wikia.com/wiki/EOScard
http://wiki.magiclantern.fm/install
http://www.ridgecrop.demon.co.uk/fat32format.htm
https://www.sdcard.org/downloads/formatter_4/

[barepixels]

I want to know too. 

what's the best practice for 64gb card and ML and 5D2

[Audionut]

If you want greater then 4GB files with ML, I would format the card as exFAT on a computer, copy the nightly files to the card, and run the ML installation procedure.
If you ever need/want to reformat the card, follow the above procedure.

[SiSS]

Okay so have I got his right:
Take 5D3 you have several CF cards for important shoot.
You know that using KB cards, it's important to keep formatting them regulary.
You have your selected ML version, you format all cards on computer and transfer files into them.
Then go?