Well, we did see the Northern lights which was a bonus. The ship is 50 years old this year, but it does not really show its age. The cruise was lovely, food excellent and we had a cabin on deck 2 that was very quiet. The cleanliness of the ship is outstanding, although I got a bit fed up with having my hands sanitised every time I went to the restaurant. Ship's entertainment was excellent with a good show band and dancers. The costumes were gorgeous. The water is eminently drinkable from taps and freely available everywhere, so don't spend an outrageous £2.20 for 70 cl of water. Bar prices seemed OK, but I am not a drinker so cannot be sure. The £5 a day per person gratuity was not my scene so I opted out of it very simply. I felt that trips were very over-priced. For instance a train ride and coach return was priced at £79. If you booked at the station then it was £25 return. Do your own thing at ports. They are not pushy with trips.
Car parking at Tilbury is pricey. I found excellent cheap parking at Justpark.com.
The booking in process was swift and efficient.