They suck to a one. OTOH, I also use soft binding (key value coding adaptors) to the whole mess. I can whip up a new dialog in a short period of time and have some lovely Table and List Models that make binding via keypaths a snap.
OTOH, when doing Cocoa development in ObjectiveC, I do use InterfaceBuilder. It rocks - but it doesn't generate code. It creates serialized object archives. When working with this, you just say something like NSBundle loadNibNamed: @"MyArchive" owner: self and it reinflates the archive using self as the "files owner" object in the archive. That rocks and the geometry management is better than the java layout managers (of which I only use Box, Flow, and Border - you can do anything at all with those).