The beaches to be honest are nothing spectacular lol we found them to be quite crowded and in some areas a bit dirty! However Paradise beach in kefalos (southern part of the island) is good, has natural bubble springs in the sea and isnt so crowded. The water sports are quite expensive roughly 40 euros for 15mins on a jet ski however our rep said this was alot cheaper than on other beaches around the island! If you go on island cruises they take you to quiet beaches on smaller islands which are nicer than the ones in the busy resorts! Definately visit Kos Town, we stayed there for two weeks and completely enjoyed the large amount of restaurants (particularly the italian in kos old town and Zorbas in Diagora Square old town) lots of shops and friendly atmosphere! Hope you have a good holiday, we did!!!!

p.s we only returned a week ago so the information given is very recent :D

pps. lol there is air conditioning in some rooms, we were with sunset and thomas cook and there was air conditioning in our apartment however it had a daily cost of 6 euros. We were willing to pay for it but to be honest we didnt feel the need as the temperature cools alot at night.