RDFa vs RDF/XML and content negotiation

I've been trying to weigh up the pros and cons of these two approaches to understand more clearly when you might want to use each.  I hope that the list members will be able to provide me with the benefit of their experience and insight!
 
So the situation is that I have some information on a topic and I want to make it available both in machine readable form and in human readable form, for example a company wanting to publish information on its products, or a government department wanting to publish some statistics.  
 
I can either: 
1) include 'human' and 'machine' representations in the same web page using RDFa
2) have an HTML representation and a separate RDF/XML representation (or N3 or whatever) and decide which to provide via HTTP content negotiation.
 
So which should I use? I suppose it depends on how the information will be produced, maintained and consumed.  Some generic requirements/wishes:
 
- I only want to have one place where the data is managed.
- I want people to be able to browse around a nicely formatted representation of the information, ie a regular web page, probably incorporating all sorts of other stuff as well as the data itself.
- I don't want to type lots of XHTML or XML.
- I want the data to be found and used by search engines and aggregators.
 
 
The approach presented by Halb, Raimond and Hausenblas ( 
http://events.linkeddata.org/ldow2008/papers/06-halb-raimond-building-linked-data.pdf) seems attractive: to summarise crudely, auto-generate some RDFa from your database, but provide an RDF/XML dump too.
 
On the other hand I find that RDFa leads to rather messy markup - I prefer the 'cleanliness' of the separate representations.
 
For any non-trivial amount of data, then we will need a templating engine of some sort for either approach.  I suppose what may tip the balance is that Yahoo and Google are starting to make use of RDFa, but AFAIK they are not (yet) doing anything with "classic" content-negotiated linked data.
 
Anyone care to argue for one approach or the other?  I suppose the answer may well be "it depends" :-)  But if so, what does it depend on?
 
Thanks in advance
 
Bill Roberts