Tool for Word->DocBook conversion (UpCast?)

All,

I've done a bit of research into this area of converting existing Word docs 
into DocBook.

The main tools I found are DocSoft's W2XMLv2 and UpCast.

I like UpCast (from looking on their website), but it says that it targets 
XML (as opposed to going straight to DocBook). There is mention on DocBook 
Wiki that an XSL can then be applied to create the DocBook result.. does 
anyone have anymore insight on this?

Does anyone have a recommendation of the best tool for doing Word->DocBook 
conversion?

Thanks,
Steve