We stayed in 6500 last August.  I think it depends on the people sleeping in that room and how light of sleepers they are.  The door is on the other side of the wall from the 2 queen beds, so it not only is loud, but also shakes the wall a bit.  We were super tired on this trip, so tried to nap in the middle of the day sometimes, and that was probably the worst time dealing with the door.  Also in the evening after dark.  We still loved the view.  I'm attaching a picture that shows the room numbers facing pixar pier.  Please note that the trees are much taller now. The green #'s are the dedicated 2 bedrooms.  I always do a live chat on 
DVC online and submit a list of specific room #'s, in preference of order.  We have always received something on that list. The last 2 trips, we have received our very first choices, so we have been in every room on the 6th floor (one trip we had the 1 bedroom and studio, the next trip we had the 2 bedroom).  It was pretty awesome!!!  <3  Enjoy!