Yes they are quiet....almost totally
We had an annoying squeak last year in big seas, it was traced to one of the bolts holding down the hard dodger. Tightened it and the others, squeak gone.
The only noise we have is from the sea running past the boat ( I quite like that), and sometimes going up wind and a bit overpowered, she slams.
We have lock downs on our opening floorboards to prevent them opening but I would have to say we have never had any cupboards come open, not even the drawers just forward of the nav station, and we have been in some pretty rough stuff sometimes.
I have never ever seen any boat that is as well constructed as our Amel SM 2000, and it was gratifying to see at La Rochelle last year the the new 50 and 60 are built in exactly the same way.