Raid 5 with 3 drives survives one dying disk. Raid 1 (mirroring) with 2 disks survives one dying disk. if either setup loses two disks all the data is gone.
When you run 3 disks then the odds of two failing are higher than if you run 2 disks.
So 3 disks are not significantly safer and might even be worse.
That being said: both setups are fine for home use, because you've set up real backups anyway, right?