If the names Steve Hutchinson and Alan Faneca do anything for you, then you'll love David DeCastro.
As talented a guard as you could ever expect to find in the NFL draft. He's big, strong and, most importantly, a technician. DeCastro doesn't live off of his athleticism, instead making his plays with great hand placement, leverage and angles.
DeCastro has the ideal size and strength for the position, combining excellent reach with the power at the point of attack to dominate defensive linemen when he fires off the line of scrimmage. If you had to complain about anything DeCastro doesn't do great, it would be that he will sometimes miss when asked to pull and hit a defender. If he can increase his hit rate when pulling, he'll be a flawless player at the position.
Worst case scenario? DeCastro makes four or five Pro Bowls.
Great value pick for the Steelers at 24, as they bolster their offensive line with one of the best guard prospects of the last decade. Will be a ten year starter in Pittsburgh.