Rayquaza V #193 from Evolving Skies is a rare card that currently sells for about $31.37 ungraded, with graded copies ranging from $13.95 at grade 7 to $20.00 at grade 10. A grade 10 copy sells for around $20.00 vs $31.37 raw. That's a modest premium, so grading only pays off for near-perfect copies.