Universidad Rey Juan Carlos is one of the youngest Universities of Madrid; because of that the majority of its campus (Fuenlabrada, Móstoles and Alcorcón) have modern buildings and really good facilities, even though those are the campus located in towns outside the city of Madrid, which makes them a little far of the city center. There are two campuses located in the city center (Vicálvaro and Arguelles) but these have older facilities than the other ones, though they are good.
About the degrees, URJC is focused on Social Sciences and Communication and there are many different degrees related to those fields and the Professors are good (even though sometimes there are lazy/boring ones). In addition, URJC is launching a lot of new degrees about gaming, fashion or sign language, being pioneer among the public Spanish Universities.
One of the best things of the Uni is its international program. You have a lot of options to study abroad or make an internship, and there are a lot of grants which you can benefit from.
Also, if you are thinking about being a exchange student/Erasmus in this Uni I definitely recommend it. There is an international office in each campus which helps the exchange students. Also, it has an awesome Buddy Program which helps you meeting local students who will help you. There’s also a student association for the exchange incoming students called Erasmus Student Network Universidad Rey Juan Carlos. They help them with everything they may need during its exchange and they also organize a lot of trips and activities.
Only one campus (Vicálvaro) has student housing but it is really expensive, so I wouldn’t recommend living there.