This is a beautifully thought out mod and the amount of work that's gone into this rivals anything Bethesda have ever done. It's truly outstanding and the scope is tremendous I absolutely take my hat off to the team behind Fallout London for their vision. However the execution is then than ideal. The game crashes or infinite loads a lot especially when moving into a new area cell. There is also a reoccurring issue with key NPCs, including quest givers, being absent from their world position and requiring a reboot to make them appear. In short I cannot recommend the concept highly enough it's truly epic, but the mechanics are far from ready for regular play and it still needs considerable work to be properly playable at the base game level.
