this is exactly why I downloaded the demos to all of those vocal plugins...
1) they let you record clean and then experiment with the sound
2) if edits are necessary, they can be done in the same environment as the rest of your song
3) they don't have to process the whole shebang.. you can edit just one small note if necessary

as I've been saying, the nice thing about a modular system like RealBand/BIAB is that you can can find exactly the modules that fit the way you work and snap them together like musical legos, and it all works together like one unified system