Boros Charm #199 from Masters 25 is a uncommon card that currently sells for about $4.44 ungraded, with graded copies ranging from $4.99 at grade 7 to $8.11 at grade 8. A grade 8 copy sells for around $8.11 vs $4.44 raw. That's a modest premium, so grading only pays off for near-perfect copies.