What may concern you: He lacks ideal size. He's barely over 6-feet and under 200 pounds so in addition to needing to add a lot of strength and weight, he doesn't have a huge frame. Whenever a blocker gets ahold of him, he has a hard time disengaging so those are some things he'll need to work on. He's better off the line than right up on it and will need to learn how to become more physical and learn to mix it up more. In addition, he's relied more on his speed and athleticism compared to his instincts to make plays in recent years.
Bottom Line: South Carolina plays in a very fast conference and they've had some fast defenses in recent years. Montgomery will fit right in from that standpoint. How quickly he sees the field will be determined based on how much weight and strength he can add in the next couple years. He's a three-star OLB prospect and a solid pickup for the Gamecocks.