Colonia and Assoluta are nice, refreshing takes on a traditional eaux (citrus and floral components, bright and somewhat shortlived). Intensa is something totally different; very little citrus or neroli. Instead, Intensa to me smells like ISO E Super and another aromachemical called Amberwood forte. I blind bought Intensa, and I find it pretty terrible. It's the least favorite of the 60+ bottles that I own.
If you are interested in buying one of these, I would highly recommend Assoluta. Assoluta on me has decent longevity (longer than Colonia), and smells a whole lot nicer than Intensa.