Going with a Superbreak ticket worked well. It was a big advantage not to have to wait in the queue, but to walk through the empty "pre-booked tickets" line. The tickets (for 3 adults and 2 children) would have cost me £51, which seems comparable to other tourist attractions.
Britannia was launched in 1953. For over 44 years, she served the Royal Family and the nation, travelling over one million miles to become possibly the most famous ship in the world. Britannia was the setting for official state visits, sparkling receptions, royal honeymoons, and relaxing family holidays. She was decommissioned in 1997, and brought to Leith Docks, where it was hoped that a major tourist attraction would help regenerate the area.
My initial impression of Britannia was that she is surprisingly small. There's plenty to see, though, and the audio guide tour lasts about an hour and a half. We took two versions of the audio guide: one for adults and one for children. Both were great - easy to listen to, informative without being too much, and the handsets were easy to operate.
Husband reckoned that it was one of the best tours he'd ever been on, and the children were engaged and interested (well, most of the time). We agreed that Britannia might not be so interesting for younger children. 9-yo pondered the question, and decided that it was most suitable for 8 and over.
It was fascinating to see the Royal quarters, and particularly to realise how our concept of luxury has been redefined in relatively recent years. The Queen herself was involved in the choice of the decor for the State Drawing Room, aiming for "country house comfort".
The bedrooms, including the one in which Prince Charles and Lady Diana honeymooned, are small and frankly rather spartan. One forgets how narrow a double bed was in 1981... I found it rather telling that the laundry, which had to do all the Royal washing as well as the crew uniforms (220 members of staff, some of whom needed 6 different changes of clothes in the same day), was never refitted. The machinery that was installed in 1953 was deemed to be fit for purpose until 1997. Ironic, really, that the Queen gave up Britannia as something of a gesture of economy.
I think Husband and I got more out of the visit than the kids. It's hard to explain to them what a previous era was like, and Britannia epitomises that era. When we were their ages, the Royal Family was remote, scarcely glimpsed. Seeing photos of them, happy and relaxed and the Queen wearing trousers (gasp), was strangely poignant. Yes, they were ordinary people, which we knew, of course, but never saw. For my children, used to seeing their own generation of Royals in jeans, visibly relaxed in the public eye, it was hard to understand that what Britannia offered a previous generation was so significant. 16-yo got it, though. As we left, he reflected on how sad the Queen must have been, when the decision was made (and I think it was her own decision) to decommission Britannia. "It had been her home", he said.
It's hard to describe the Royal quarters. The spaces are both regal and informal. Even the State Dining Room, used for state banquets when the Queen was on tour, felt small and intimate. On the walls are gifts that the Queen received on her tours, including a narwhal horn (who knew you could see a narwhal horn in Edinburgh?). There's also a whale rib, picked up by Prince Philip from a beach in Antarctica. I found these little details absolutely fascinating.
The tour also shows you round the crew's quarters. You can marvel at the cramped existence of the ratings (bunk and one small locker each), and the pristine formality of the officers' dining room, complete with impressive silverware ("No TV dinners for them!" said the children's audio guide). It is apparent that the crew loved the ship; there was a strong spirit of loyalty, and also fun. In one room, you can see the toy wombat that the crew used for their evening entertainment of wombat tennis, and a button from Lord Nelson's coat in a frame on the wall. That sums up a tour of Britannia: in the same room, details of the daily life of a much-loved working vessel, alongside history and grandeur. Britannia was an ambassador for Britain round the globe, hosting meetings and events on the world stage, but also the family's holiday ship, pottering round Scotland's Western Isles, with the family and Captain deciding each night where to go the following day, and good picnic sites noted down in the Captain's diary for use in future years.
The Britannia website says:

