It's a concern that some of his policy positions seem to be based on self-interest, though he's not as egregious as Trump. At least he's in favour of higher taxes on the rich.
That said, he might be the candidate best able to beat Trump. I certainly think he would be the opponent Trump most fears. I doubt the stop and frisk thing would hurt him in the swing states they need to win back.
It's interesting that we're all so focused on which candidate would be better able to beat Trump rather than who would make the best president. The man who thinks everything is about him has succeeded in making his opponents' selection process mainly about him.
https://www.theguardian.com/commenti...t-donald-trump