BOSSKEV I hate not tried this company's product. However, having looked at their website, I have two comments:
1) ALL of the voices they feature are sourced from Cepstral, presumably used by TexSpeech Pro via a license from Cepstral. I am very familiar with Cepstral voices as I own and use several of them. And anyone can buy those same voices direct from Cepstral. (BTW, the best ones are David, William, Callie and Diane. Or, for a British accent, go with Lawrence and Millie.) (I LOVE Millie!)
2) Mac OS X has excellent text-to-speech capabilities already built in, and it works seamlessly with the Cepstral voices. No other software required, just the Cepstral voices.
So...uh...why would I buy THIS product? I'm not saying I wouldn't or that you shouldn't, it just is not AT ALL clear to my what added value they bring to the table.
(Version 3.5.2)