The mod seems like a whole new game and in terms of the story, it has the same quality like Fallout 4. The setting in London is really a great idea and it's a awesome exploring the sights like London Eye, Trafalgar Square, Tower Bridge and so on. I am now level 16, did a dozen of quests and nearly discovered round about 40-50% of the huge map. I guess, you can spend a really large amount of time in this game. And the best. It is free. I had some crashes at the beginning. But this was caused by a unclean deinstallation of my previous (modded) Fallout 4 version. Now it is running smooth with the same amount of crashes i had with the original Fallout 4.