IMHO Subban professional future will come to how coachable he is. He has a lot of very intriguing tools, a great attitude, and the heart of a Lion. But can he accept to "re-learn" the way he plays in the pro, without relying on the same kind of high-risk plays he's known for? I fully agree that he's a boom or bust prospect.
He he ends up with a good coach who manage to make him understand the importance of steadiness and constance in the NHL, then he's a future top-2 blueliner. But If he ends up in the AHL, high on his junior numbers, and refuse to reconsider the way he plays, he won't be as succesful.
The good news is that he does seem to have a pretty good head of his shoulders. He's already much better defensively than last year, and he didn't look bad at all during the habs training camp this fall.
One thing for sure, his personality is refreshing. His supreme confidence and demeanors reminds me a bit of Ali.