We called in to see the castle while in Wales and found ourselves there for several hours even though, on the face of it, there isn't a massive amount to see (albeit the castle is very big).
The most impressive thing was the interactive table that provided photographs and a great deal of information about the history of the castle and it's restoration. My husband and I spent a lot of time on this, but I did think that if we had been there at a busier time (we went on a Monday morning) we wouldn't have got near this table, and information elsewhere about the Castle is very limited.
There is the odd board about here and there but I think there should be more information in the rooms about what they were and who used them. Almost everything we found out was from the interactive table and the guide book, the latter of which was difficult to follow and needed updating as parts of the castle have been opened up and are now accessible since that book was written.
National Trust properties I've visited provide a tour tape with headphones and something similar would have been really useful here.
Overall I'm pleased I visited as it was really interesting. A bit more easily accessible information about the history round and about (in addition to the interactive table that only a couple of people can access at the same time) would be helpful though.
Warning - this is not a site that is wheelchair friendly.