I agree, it is worth doing both. I do strongly advise to get the Extended Edition cut of the LotR movies as it elevates them even more.
For the best quality there is the UHD Blu-Ray box-set that contains both cuts of each movie:
BUT
For lore and history purposes I would ALSO get the Blu-Ray extended edition box-set that contains many hours of extra content, documentaries and interviews, etc…:
Shop The Lord of the Rings: The Motion Picture Trilogy (Extended Edition) [Blu-ray] [2001]. Everyday low prices and free delivery on eligible orders.
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