Antenna House Formatter - customising extensions

I'd like to move from RenderX XEP to Antenna House Formatter because
    it seems to offer better typography and page layout for complex
    material. But looking at their website, in particular the axf
    extensions available, I can't determine whether:

    1. all the extensions come bundled with the formatter out of the
    box, or 

    2. if there are supporting stylesheets available at cost I need to
    integrate with my customisations, or 

    3. if there are only examples of stylesheet implementations
    available for individual extensions, which I would then need to copy
    and somehow get to work with DocBook.

    

    I've read a few posts about others who were looking at AXF - which
    of the options above is correct? I need to know if what I spend on
    the formatter is going to be good value, or if I need to still put
    in a lot more effort and dollars to get the extensions working.

    Thanks!

    Dave

    
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