The Water Temple is only annoying to one who doesn't like solving puzzles. I kind of have a knack for that, so I found it quite entertaining. It is often discussed as being the hardest dungeon of any Zelda game; however, I didn't find it as hard as a few dungeons such as the Great Bay Temple of MM, which I found to be quite annoying, but really entertaining once I got the hang of it. The Water Temple isn't really the kind of dungeon that I had to spend 5 hours on, because the puzzles in it were not overly confusing. But, it was hard enough that I was pretty much zoned in to the game and I had a great sense of accomplishment once I completed it. But, for what seems to be the majority of people out there, that don't particularly enjoy challenging puzzles, I could see it being quite a difficult and annoying dungeon.