You're right, Nina was awful, but that's in a different class, to me.

It's part of the deal with the viewers that awful things might happen--we knew that from the start, at the beginning of the very first episode when we saw the failed resurrection attempt. And it's also expected that *minor* characters might turn out to be other than we think. But Ed and Al are the emotional foundation of the series--they're the reason why we watch. More, Al is the _moral_ center of the series. And like you said, poor Al: restoring his body is the most important part of the quest--so if that's not Al's soul in the armor, then you lose both the plot *and* the emotional connection to the series.

All that said, this is just my opinion--I'm not saying that I *know* what's going on, certainly, and I can't wait to see the next episodes!