Audition definitely has an advantage over CEP: VST plugins. I'm a former CEP user, and was very happy with the upgrade to Audition. Improved GUI to say the least.
That said, I'm not sure if Audition 3.0 can run on W7 64 bit. It does on W7 32 bit. Hopefully, someone can chime in, who uses it with 64. If no one, then I'd wait for Audition 4.0, which I'm guessing, is gonna debut next spring/early summer. That should have 64 bit capabilities.
It runs on Windows 7 64 bit, but I have a strange issue it eventually eats up all available memory when editing 24bit files.
What's happening is that your 'undo' buffer is filling up and using up all of the available free space on the drive that holds your 'temp' directory. This actually is not unique to 24bit files...it's true of all versions of Audition and all files. The reason you see it with 24bit files is because those are much larger files than 16bit files, so the undo buffer fills up alot quicker. In order to prevent this from happening, you need lots of free hard drive space and the temp folder has to be assigned to the drive with the most space. Alternatively, you can kill the 'undo' function, but then of course you won't be able to fix any mistakes you make.
Here's what I have to do in Version 1.0 to change the temp directory to another drive to keep this from happening...
1) First go to the drive with the most free space and create a 'Temp' folder in the root directory or verify that one already exists.
2) In Audition, go to 'Options > Settings > System'
3) Near the bottom of the window, under 'Temp Folders' navigate to or define the Temp Folder that you created above...
I'd recommend the above over killing undo. However, if you want to disable the undo function, that's simple...
- Edit > Enable Undo/Redo > Click 'OK' when you get the 'are you sure' pop-up window.
You can always turn the undo function back on whenever you need it.