Both are good in their respective applications. Sound Forge is good for recording, editing and modifying individual files. Our first SF job, for example, was 15,000 voice cues for an educational CD ROM. I have also used it heavily on a series of syndicated radio features.
Sound Forge is weaker, however, when it comes to mixing multiple layers--especially longer files. You, you can mix, say, a voiceover with a piece of music and add a few sound effects, but once saved, the mix is 'locked in'. When the client decides to change or delete a phrase in the voice, you'll be going back to an earlier step--maybe even the beginning--to rebuild the file. You can save all your intermediate steps as separate files, but that takes time and disk space.
Vegas, on the other hand, is a non-destructive multitrack editor. You could deliver a finished product, then go back later and change any event later without penalty--even create multiple versions for different uses.
I think you'll find that the two products are highly complimentary, and I, for one, plan to use them both for their respective strengths. It's useful to note that they share commands wherever possible, so you won't be switching brains every time you decide to open a Vegas file in Sound Forge to hammer out a special process in that program.
>>could anybody telle me what software is better?
>>Vegas or soundForge.
>>Thank you all