I bought and use Sound Forge Audio Studio 10 ($64.00).
I didn't see the justification for SF Pro 10 for me right now mostly due to the cost, since SF Pro 10 is $499.96.
Here is a comparison chart:
http://www.sonycreativesoftware.com/audiostudio/compare I mainly use Audio Studio to convert my audio files to different formats and both products will save in those different products.
Sony has an upgrade path for SF Pro 10 for $319.95. Still cheaper than buying SF Pro 10 outright as SF Audio Stufio + SF Pro 10 Upgrade = $383.95.
It's really stable easy to use and just works for me.
What did you need to know or were particularly interested in it for?