I used the AArivals lounge last Saturday - just for a shower. Super clean and huge shower suite. Had my shirt valet ironed and trotted off to T5.
It was really quiet in there (about 12 noon) - I didn't walk through to the lounge and dining area. The member of staff on reception was very helpful and assisted me in rebooking to NCL - AA protected the connection for me across 2 PNRs