More because IMHO both are incomplete, and they each cover areas that the other skipped over, the original because iirc it finished before the manga, and brotherhood because, at least it felt to me, like it glossed over some areas that the original covered already
Brotherhood intentionally skipped over a bit in the start, since people most likely had seen it. Not enough for me to recommend watching the entire older anime though. Maybe up to a certain rain moment.
Because the ending to the original is so unsatisfactory?
More because IMHO both are incomplete, and they each cover areas that the other skipped over, the original because iirc it finished before the manga, and brotherhood because, at least it felt to me, like it glossed over some areas that the original covered already
Brotherhood intentionally skipped over a bit in the start, since people most likely had seen it. Not enough for me to recommend watching the entire older anime though. Maybe up to a certain rain moment.