Metroid Prime is fantastic, the best Metroid game along Super Metroid. Glad you enjoyed it.
Other M is a good game, but not a good "Metroid" game. It tried a different formula and I enjoyed it for what it was, but definitely had some negative points like:
-Very linear
-95% of hidden items are missiles
-Lack of music
But I enjoyed the story and the gameplay so I still recommend it.
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