Bleach vs fullmetal alchemist   stance: fullmetal alchemist:
They aren't really on the same level.
Sure, Bleach is an enjoyable anime/manga but when you look at anime's the quality is vastly different.
FMA's storyline was set strongly to the 51 episodes, and was never based entirely on the manga. The finite number of episodes is one of its greatest strengths, as storylines that chug on for ages eventually lose steam.
Bleach is now in the 160's if I recall correctly, and a large portion of those are rather daft filler episodes as they try to keep up with the manga that the series is bound to.
The stretching out of events in each episode makes the show feel like its dragging its feet week to week, whereas FMA managed to keep things rolling strongly. Watch other shows like Tengen Toppa Gurren-Lagann (which had 27 episodes) or Flame of Recca (which had 42) and you can see why a limited number of episodes can add major strength to a series.