I suppose the subject asks my question but to give some more details, what would I be able to do with the combination of SFS6 that I can't currently do in Vegas?

I am planning on picking up Vegas 4 (the Academic Edition if there is one) and I also own Sound Forge Studio 5 that came with the Digital Video Book by SonicFoundry so I could pick up Studio 6 for $30. I haven't used version 5 at all yet, still exploring Vegas, so I am not really sure what it offers. I have used CoolEdit in the past. It would be nice to silence out loud noises in the video, which I currently do in Vegas with the volume envelope.

Thanks for any comparisons.