Most cichlids will get aggressive when spawning, but if not breeding, they can be quite docile.
I guess I have been lucky, I've heard lots of stories about people with bad rams, I found mine easy to keep. There are some very poor looking ones out there I must admit. I know there are wild ones that have been imported recently, so the quality is getting better.
Like caserole said, raising ram fry can be tricky, it's no problem if you keep up with the water changes and pump food into them