Miraidon ex #28 from Scarlet & Violet Black Star Promos is a reverse holo promo card that currently sells for about $1.50 ungraded, with graded copies ranging from $3.00 at grade 7 to $50.00 at grade 10. A grade 10 copy sells for around $50.00, about 33× the $1.50 raw price, so high-grade copies are worth grading.