The original Spanish cast had some of the most important voice actors in the country. The best example is Willy Fog's voice, Claudio Rodríguez, who was famous for being Charlton Heston's recurring voice actor in Spain and more recently was Dumbledore's voice in the Harry Potter movie series.
The Czech cast was absolutely stellar. Even the minor characters like gentlemen in the club are to be recognized by most viewers of various ages, and there are no questions asked about the main characters. The protagonist takes the cake, because Viktor Preiss, who voiced Mr. Fogg, is one of the most respected actors of his generation.