I liked Laura Bailey a lot, she did her character perfectly and sounded very sexy.
But Rebecca Sanabria was the best of them all. She was the only female voice in both TT and IV which didn't sound so sexy, but more insane and lunatic. It fitted my character perfectly (it was a tomboy).
I was really disappointed when I found that she won't be in IV. Now I can't use that character because it feels weird (I had to use my other one which had Bailey's voice), but IV's setting was perfect for the first one.
I hope we can eventually have a voice pack DLC with Sanabria and some other stuff (I remember Volition scrapped a fully auto-tuned voice for the character, much like Zimos's voice)