sys-fs/exfat-utils-1.2.4 is in tree for > 30 days, been using it without problems on 2 of my boxes. Last stable 1.0.1 is from 2013. Since then many bugs got fixed: https://github.com/relan/exfat/blob/master/ChangeLog
*** Bug 589604 has been marked as a duplicate of this bug. ***
Please stabilize: sys-fs/exfat-utils-1.2.4 sys-fs/fuse-exfat-1.2.4
amd64 stable
x86 stable All done, closing!