Metroid Fusion's a blast. Linearity be damned, the game's controls and movement are incredibly polished. Simply going from point A to B has never been more satisfying, the sound design as Samus jumps around adds to how night and day the movement feels compared to its predecessor. Super Metroid was great, but the control scheme could've used refinement and Fusion happily takes notice. No more swapping between your missiles or power bombs. Hold down R when walking around (or in morph ball form), press B, and let the booms begin!
I only got 45% of the items on my playthrough, which has me tempted to boot up the save, go item hunting, and collect everything else. Fusion's solid in the replayability department, my playthrough only taking 5 and a half hours. Lovely game that, of the 3 games I've played through to completion so far, it's between Prime and Super. All great games, but Prime takes the cake for me as a solid translation of the Metroid formula into first person.