Sherman's negatives probably out weight the potential positives at this point, but the panthers might feel it's worth rolling the dice. For anyone worried about how this might fug everything up, the Panthers have shown they'll cut someone's ass if they don't fit in with what they're doing; see Perryman, Denzel
My personal opinion is that he's worth bringing in, if he has his personal poo under control and he understands his role on the team. Some players (like peanut) are willing to embrace that leadership role. Some players (like steve smith) are not. A lot of his recent issues have reportedly been related to a mental health emergency, and I'm not going to poo on someone for that. If that's under control, and he feels it's under control, I believe/trust him. He's a cerebral guy.
Additionally I'm glad to see the panthers FO is on the same page as me. Now let's sign some big workhorse RB and shift CMC to WR.