In my very humble opinion, it is the best fishing game (of the few) on NES. The level-up system and random events during fish fights give the game much more depth than Hot-B's other NES fishing effort, The Black Bass.
In this video, I spend a good amount of time describing the mechanics of the game, and I surprised myself with how much explaining was required. The game is deeper than I had previously imagined.
To make the video more watchable, I made some cuts before recording commentary to eliminate some repetitive boat trolling and one long and unsuccessful fight with a marlin.