I have a love-hate relationship with Navi. I am playing Orcarina of time 3D at present and she does help a lot when it comes to defeating enemies and/or bosses. In the other three games in the Zelda series that I have played (Phantom Hourglass, Spirit Tracks and Twilight Princess), none of the companions really ever provided me with hints on how to defeat them, expect for whenever midna would give me hints if I was doing something wrong. So that's really handy. Navi's noises don't really annoy me all that much either, since i normally am so concentrated on completeing the game that her voice become more ambient sound. However, it can irk me when she reminds me for the fifth time to ask Saria about the third Spiritual Stone, even after I have played the song twice and asked her twice.