I went for a week in Oct 2011 with mother and aunt, booked with Thomson. It was our first experience of AI.
First the positives. The welcome, arrived around 915pm, restaurant still open for us. Our room was ground floor, garden view, had own pool and comfortably accommodated 3 adults (albeit I slept on sofabed). Modern, clean rooms, endless supply of bottled water. Food and drink abundant, how they managed to deliver so much food and drink amazed us. AI drinks clearly marked on bar menu. Plenty of sunbeds (but may be different at height of season!), beach towels. A la carte restaurant good, if limited menu (one visit per week per stay). Above all, nothing too much trouble for staff.
The negatives. Two days bad weather (not their fault!) so on one day had to move lunch from taverna to main restaurant. Insufficient seating in main lounge area meant guests either sitting on steps or too far away from entertainment. Restaurant at dinner very loud, perhaps some softer lighting, soothing background music would have tempted people not to shout! Animation team disappointing, didn't know what to do during the bad weather.
If you want to go into Kos Town, bus stops outside hotel. Buy tickets at Reception as up to 30% cheaper than on bus. Rep will give you a timetable. Nothing in vicinity except go-kart track. Be cheeky about an upgrade, but you may be lucky like us and get a good room. The reviews on another site (can I mention Trip Advisor?) are very helpful, I've also posted there. Would return!