we stayed at Zygos 2 weeks July / August. Although hot the constant breeze made it comfortable. Roof top pool was perfect, very clean, lounge beds umbrellas etc. The owners were very nice and Carol [ from Wales] was just wonderful.
Sissi is a lovely little town with enough good restaurants for a two week stay. We had good food every night and typical cost for two was around 28 to 35 Euro including wine. Car rental from the place with the big smile on the sign was very reasonable. A 3 day rental takes in most of the places. Recommend the Plateau, a scarry drive up but well worth it , allow a day for that.
The best beach we found was in Malia before you get as far as the town and the rowdy section. You can walk along the cliffs from the hotel , about a 1 hour walk each way, take decent sandals as its a bit rough going. All in all we really enjoyed Sissi, nice friendly hotel, nice guests, good food and great weather and very friendly people of Crete. Peter and Mo, DurhamMore