Ok, so it lives up to it´s reputation.
Buying the tickets can be tricky, so here is the story. 13 euro for the full visit. Buy your ticket onlin a week ahead of time. We arrived on site at 9 AM and bought the tickets in the automatic booths at the foot of the first parking lot. Make sure you take the 6 euro audio guide it makes it more interesting with 36 stops.
We left at 3 satisfied, hot and sweaty. Beautiful gardens.
Here is a detail of the countless waterworks in La Alhambra.