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It works well. For plain vanilla computing I find it a tad faster than either Parallels or VMWare. However, its feature set is somewhat lighter and it is less compatible with certain peripherals.

A mixed bag - for office-type applications give it a try, you might find that it does everything you need. If, however, you want to play games or use anything that requires DirectX, then I'd go for one of the commercial solutions.
 
Works really well with Windows XP and for office stuff, don't see any reason to use Parallels or Fusion (in my case).
 
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