Castro took a prosperous nation and turned it into a socialist basket case. Pinochet took Chile and turned it into the best economy in Latin America.
Yes, Pinochet made mistakes and there were excesses. Yet, he accepted a public plebiscite in '89 and left power. Since his departure, Chile has had several elections.
Castro has never had a plebiscite. He will die in power and arbirtrarily transferred power to his brother.
Dictators are dictators. Yet, Pinochet will have a much longer impact than Castro.