I have been using snapraid on my ~amd64 system for several weeks now and it works fine. It synced over 5TB of data, manages frequent updates on them and have successfully undeleted files (confirmed by diff with the original). Never had any problem, warning, crash, etc. So I think the ~amd64 keyword can be added without problems. It is a great utility, much better than other RAID solutions for home setups imo.
done