The check-in process was very smooth. We were delighted to be offered an upgrade that was more spacious (a touring van). This suited our needs perfectly. However, please give yourself extra time for the return at the Madrid Barajas airport (Terminal 1). There was 1 person jockeying between the desk AND the return lane. We waited over 15 minutes for the return, eating into our window of extra time for the airport. National, get more people working there during peak hours.