Sell or continue to hold?

Lived in the middle of no where when these originally came out and just picked up a set every week from my Walmart figuring the art was great and they would be worth something someday. Seeing current prices getting close to $500 a set? Do we think it will go higher or settle back down?

Lived in the middle of no where when these originally came out and just picked up a set every week from my Walmart figuring the art was great and they would be worth something someday. Seeing current prices getting close to $500 a set? Do we think it will go higher or settle back down?