Statendam is an older ship, but just out of dry dock before our cruise. Spic and Span clean. Air conditioning, as mentioned in other reviews was fine in our cabin, but very uneven throughout the ship - roasting in dining room, freezing in showroom. We did, however, speak with people who had big issues with the temperature in their cabins - either too hot or too cold.
Food was excellent, menu varied and everything delicious. Entertainment is usually on the weak side on Holland America ships. This cruise was an exception. Shows were varied and excellent, performers were very good.
If you need variety and lots of stimulation, this is not the itinerary for you. The first week had only one port, the rest were at sea or transiting the Panama Canal. Weather was great, so we enjoyed sitting in sun and shade, the pools and enjoying the extensive library.
deck 5 cabins have the beds under the promenade deck 6. Usually not a problem unless there are very keen power walkers or runners (which is not allowed) at 6 am. I almost went out in my pyjamas to chew them out!
686 is quite far aft, so you get engine noise and thrusters when coming into port. Not a big problem, however, for people who like to know when we are getting into port.