I'm just back from a week in Plakias and a week in Sougia; I slept with the windows wide open, didn't resort to mosquito coils, Jungle Formula or anything and got maybe two or three bites in the whole time. Not once did I get woken by that incredibly annoying buzzing in the ear. I must admit I do normally eat a lot of Marmite, though didn't take any with me ...
I wonder if the beasties might be losing their natural habitats to climate change? For instance the Rough Guide refers to a "stream" at the eastern end of Sougia which at least in July is just a dried-up bed.