Like anything, it CAN be hurt, but it takes a lot of abuse or poor setup. My dana took a lot of abuse, but after many trans brake launches needed new gears. The old ones cracked. A friend broke two dana gearsets back to back. I am certain something was wrong with his install.
I didn't post to rain on your parade, just the opposite. A great rear, just needs good care and setup when changing gears, and will last a very long time!! Enjoy