As a local who has also travelled a lot I have to say I think the PumpHouse is pretty embarrassing. Belfast has come a long way in terms of tourism and also in terms of customer service which the UK/Ireland in general is pretty bad at. The new Titanic Museum is worth a look and paying for - I can't vouch for the tour of the dry dock as I havent done that myself yet, though as some people pointed out you can look at the dry dock yourself without having to pay for a tour. I just think the building itself looks dilapidated on the outside (yes, I know its old and authentic, but could it be washed or something?), the inside, cafe etc. is cold, bare, uninviting, and food/coffee is really not great. It has the atmosphere of a canteen. You kind of expect it might be cosy or try to recreate the atmosphere of an old tea room or something, its not even an averagely nice coffee shop. Doesnt add to the whole experience at all.
This review is the subjective opinion of a TripAdvisor member and not of TripAdvisor LLC.