Generally doing an AFF has been one of the best choices I've ever made. It didn't feel that way in the beginning of the AFF-course as my body didn't consider jumping out of an air-plane as a natural thing but it changed during the course as I got comfortable with falling out of the sky.
My instructor was good in explaining skydiving itself and in finding solutions and exercises for my improvement. However he was quiet rough in his first feedbacks creating more an atmosphere of drill than the relaxed environment that you would need as your body and mind are already in a alert state. Luckily that changed completely after addressing this. Respect for his ability to adapt his teaching style to the student.
However, now that I've been to different dropzones I know that other SkyDiving Schools teach you a lot more during your AFF for a comparable price. In Hohenems (Austria) which I can strongly recommend you if you speak German, you learn to pack your parachute as well as the first elements of relative work. That makes you much more of a skydiver once you finish your course.
The spirit on the dropzone was great which helped a lot to chill out between the jumps. Everybody was friendly and open minded - I met a lot of interesting people I'm still in contact with. The dropzone had everything from a bar where you could buy soft drinks, coffee and sandwiches to a full restaurant with a great three course meal for just 10 €.
Beside jumping and having fun there was nothing to really think of as everything else from transport (daily and airport) to accommodation was perfectly organized by the FFU for a fair price.
If you are looking for an option to learn SkyDiving before/ after summer Madrid is surely an option. Otherwise its worth to have a look at other European Dropzones (as Hohenems or Sevilla for example) as they do not only try to bring you through the AFF but teach you a lot skills beside that you'll need later on.