To be honest, rating for Alogomantra beach should be lower, if not much lower.
The water is not clean (a problem with all northern beaches, and I don't understand why), and you'll have a pleasure of swimming with plastic bags and other objects.
The right part, with a nice huge rock with a hole is small, but still very popular among young people, so you can expect to find it full of people and well, full of screaming.
I gave it higher rate only because the right side of it (although nothing special), is mostly abandoned, so you can enjoy in peace, plus the beach is sandy and tame.
And the small beach looks great with that huge rock.