We sailed on the Arcadia in August last year but only on a mini cruise from Southampton to Bruges for 2 nights, so had very little time to explore the ship.
On the 10th March this year we flew to New York & boarded the QM2, sailing to the Caribbean for 10 nights. This was our first time with Cunard. We've cruised about a dozen times before with P & O, Princess, NCL & Orient Lines. We had booked a B3 Grade cabin (sheltered balcony) but got upgraded to a De-luxe balconied cabin on deck 11! We should have sailed in January, but sadly my Mother passed away on the day we should have departed. Cunard certainly made up for this. Beside the upgrade we were given champagne, chocolates, a vase of flowers and after dinner on the first evening, I was presented with a birthday cake as it was also my birthday when we should have originally travelled! I can't image any other cruise line going to so much trouble. We were so impressed as you can imagine.
We dined each evening in the Britannia Restaurant (cattle class as my partner refers to it). The Restaurant was very impressive being on 3 levels. The food was by far the best we've ever experienced on any cruise line before. We did have a problem with the wine though as Cunard's suppliers had let them down in New York.
The facilites on board were excellent. The cabin was the largest we've had before. We don't take advantage of the shows in the evening, but the frinds we made at dinner were very impressed with them. Although there are obviously a large number of passengers on board, as the ship is so vast, you never feel cramped.
We would certainly hope to travel on the QM2 again!
As regards the transfer from Brooklyn to your hotel in New York, we caught one of the Yellow Cabs which wait outside the Terminal. There is a set charge of (if my memeory serves me well) $45.