Yes, N3DS systems have had outstanding results with the newest sysupdater linked in the tutorial (Julian's version).
Very simple:
* optional * backup saves with SVDT
format system
downgrade
Choose emuNAND or not
reinstall games
* optional * import saves from before with SVDT
DONE, and with the optional steps, no save data lost.
With the system format, and the newer sysUpdater, there have been no hardbricks yet (aside from user errors regarding installing o3DS to N3DS updates).
Very stable with 80% success rate, and ~20% softbricks that are easily remedied via the safemode restore and try again.