WYSIWYG Map eiditor

Ok, first off, I know about MonkeyWorld3D.

But I was wondering, since I haven't tried the latest version… how you guys make maps with walls and geometry easily?

Because hard-coding is too much trial-and-error.

Do you guys use MW3D or what? From what I remember it can't make terrain yet right?

I believe most people either use MW3D or use models.