There are many detailed reviews on the site and therefore, I will keep mine brief and simple.
This was our 12th cruise over all and we believe the ship was over hyped and heavily marketed, but sadly it under-delivered big time.
Pros:
Nice decor
Very good food
Comfy beds
Respectable selection of shops on board
Good selection of books in the library
Good selection of on-demand movies and shows (but not many live tv channels)
Limelight lounge - Kiki Dee performance was a highlight
Cons: (first of all, let me say that there were endless broken down/out of order facilities/amenities on the ship to list them all- from broken down lifts to out of order boiling water/tea machines to broken toilettes .....and the list goes on - hard to believe it's a brand new ship)
Small balcony, very dirty with seas salt residue all over the balcony furniture and windows, the balcony was never cleaned
Compact on-suite
Tiny casino
"Some" rude staff
Very few onboard activities
Expect to pay for port shuttles
Very weak hygiene enforcement
No mid-ship staircase
Very squeeky areas oo the ship and in our cabin
The theatre entertainment was ok but the music was very loud and the seats were narrow and uncomfortable. Get there atlast half an hour before the start of each performance - Big ship and not many seats to accommodate everyone.
Would we sail on Britannia again - not in the near future. We paid a lot of money for this cruise and expected a lot from Britannia but sadly we left feeling over charged. Sorry!