The white dress doesn't flare as much...that may be why it wasn't as flattering. I'm not sure I would even call that one a fit and flare.
The one you are asking about would look great on a pear. And like the others said, don't give up on a style if the first one you try doesn't work. There are often other factors in the way it is cut or constructed that may make some examples of that style work for you, while others don't. If I like a particular look, but the first try looks like a disaster, I tend to keep trying that style every so often anyway. (I'm stubborn that way.) Sometimes, eventually, I will find an item that works. And I usually find that the difference is because I've found an item that is proportioned slightly different from the others.