We have just returned from a 4-night trip on the QM2 to France and Belgium (M429). We will not be booking for any longer trips. The ship is beautiful and the 'ride' is probably the best we have ever had. However, the attitude of the company seems to be 'Give us your money but we're not bothered about you'.
Plusses first: (1) the cabin (Deck 11) was a good size; the beds comfortable; storage space adequate (though no hangers in the 2nd wardrobe); shower bigger than on many ships; pale wood decor very pleasant (thought it would have benefitted hugely from some hooks somewhere on the walls for coats - and from the addition of tea/coffee-making facilities). The balcony was spacious and private.
(2) Staff were generally helpful: Maxim, our wine waiter in the Britannia Restaurant was especially so. His knowledge of wines, attentive service, and careful judgement of when/how long to engage in conversation could not be faulted. Room service was excellent. We enjoyed a continental breakfast in our cabin each day as well as ordering a late lunch on two occasions to avoid the abysmal experience of the buffet.