In the last 5 years, I've had corruption with cfw+exfat, ofw+exfat and even cfw+fat32. I don't think any combination is 100% safe.nop Stock Firmware do not works fine with exFAT, is equal prone to corruptions like on CFW, because the culprit of the corruption is the NINTENDO driver on OFW, could be you "felel" what the corruption happens more often on CFW because if you are on CFW you trend to do more things on the console, but the chance are equal.