I ordered two round trip airport-Puerto Juarez shuttle tickets and got the discounted Isla Mujeres ferry tickets through the discovery mundo website. Our experience being picked up at the airport was great- fast and courteous. We were given two one way tickets on the ferry for use when we arrived at the ferry. The issue was on the return. The ticket window at the Isla Mujeres ferry terminal did not accept the online receipt for the round trip ticket so we had to pay for a one way ticket. Unnecessary cost due to poor organization. They claimed to not know Discovery Mundo. We tried calling customer service, but the hold was too long and we did not want to miss the ferry. Too bad. The return shuttle was great.