Sergio is a really nice person. Friendly, helpful and he can tell you really interesting facts about Astronomy. I'd recommend him with no doubt.
We wish to meet him again in the future.
Nice and respectful person. I 'd recommend Sergio to any host.
Sergio, Claudia, Carlos and their friend left the flat in a very good condition. I've been told they have all been very nice and friendly. They can come back next year if they have another similar conference in Aix !