Yeah, even PMing a link to the vox mentioned would probably give you the best response .. you could hear different attempts with different tools pretty easily and affordably.. without any $$ outlay.

I guess you may have 'rights' concerns, but if you are selective your exposure is pretty limited.
Otherwise these type of discussions can become pretty subjective. A simple sample to tinker with would let you see what is possible with tool A and B. I'm sure people here would pitch in. If it's background vox, having them not being too 'real' may be OK .. or not. Many times when BG vox sound good in a song, you may be surprised how they sound when soloed. Same applies to a good bass track a lot of times.

I do not work here, but the benefits are still awesome
Make your sound your own!