..think of a reason why I would wanna even keep VV3 on the computer when I now have acid 4, soundforge 6, noise reduction 2 and CD Architect 5, and all the most recent updates..? I even have sonar131 "sittin it out" for awhile; less to sort out, I guess...
The real question is WHY you got Vegas in the first place IF your only interest is audio. Vegas is excellent at BOTH audio and video while the other applictions you mentioned either only support audio or only support video in a limited way. Again, Vegas supports BOTH audio and video very well.
ACID isn't multitrack audio, can't record/monitor at the same time for long projects, can't do mono in ACID, can't have muliple events on a single track in ACID, Forge isn't multitrack, and SONAR 1.3 can't touch Vegas when it comes to audio.
I use Vegas for most sound things and am just learning about video now and really loving it over the application that came with my Pyro card. (premiere) Because it's fairly easy to learn the basics on. But for audio Vegas is still our most often reached for tool and we have ProTools for the PC as well. Vegas beats it easy.
IMHO
Well..at the time I had acid pro 3, sf5 and sonar, there was no mention of CDA5, and CDA4 looked OK, and everybody was waitin on A4 and SF6; I threw my weight to VV3 because "someone" in the forum (or perhaps in the cakewalk sonar newsgroup) mentioned that it was a good "macro" for audio applications...and I can see that they were right...
First of all, maybe you should ask that question on the Vegas-AUDIO family.
Second of all, I can't see why you would need reasons from fellow forum users. If you can't find a reason why you should keep it, then either all the other programs satisfy you needs, or you don't know the software enough to see why you should keep it.
It seems to me like you've got quite the arsenal there. Why not keep VV3 for the (maybe) few times you find you need it?
I have to say that for multitrack audio Sonar 2 is wonderful. Rock solid. Low latency. DXi and VST/i (with wrapper) support. Looping. Sequencing. Support for many different control surfaces. Dead simple to record in. I love VV3 and Sonar 2 for different reasons.