We got back from Stena Apartments last Wednesday and had a fantastic time.  The rooms are basic but very clean.  They are a great starting point to get to the pool (at Kontessa) and to the beach and super markets (all 5 minutes away).  The bus stop is around the corner which takes you to paradise beach and kos town.  (its worth getting the speed boat over to paradise beach - which takes you everyday at 10.30 am).  Would definitely book these apartments again.  Kefalos is lovely, you can either have it quiet or lively in the evening.  Everyone was so friendly, especially Maria at the restaurant/bar Acropol.  Next time I think we will have to hire a car as we did not get to do much sightseeing of this beautiful island.