He could be, at worst, the next Anthony Bennett, or the next Shawn Kemp. Not better than Kemp for sure.
RJ is far better than Zion now. The kid from Indiana (Langford) also seems to be more complete than zion
That said, the kid have good IQ, he's not a clown. He is going to have a long career at the NBA.
If he improves his shot selection, I see 15 and 7 for his freshman year under Coach K.
The free throw line dunk? It's great. And many people did that. Including players like Jonathan Bender, Gerald Wallace, Brent Barry, etc. But -for example- Brent Barry had a long career in the NBA because of his outside shot. And he was avoiding dunks after all. The landing hurts...