Iv'e only done The London Dungeon and The Castle dungeon (which I do quite frequently as I live on the outskirts of Warwick). I think Warwick beats it for me, it might not be as long an experience but the theming is far superior in my opinion (as it is in a real castle!). Also, the atmosphere is much better because as opposed to London, Warwick hasn't got the whole "Fear is a funny thing" tag ling and instead it is very much percieved as a "scary" attraction; with a much more foreboding entrance, lots of narrow ancient corridors, all the cool wax figures that vomit and rattle their chains as you go along and overall just a much more claustrophobic and real vibe, The Castle Dungeon excels at atmosphere. Oh, and do I even have to mention the finale? In conclusion, Warwick is my cup of tea.