I'm using it right now while I edit the TSS2 voice acting and this tool is a godsent.
The generated speech is clear and loud (which is a good thing, because it's easier to pitch something down than pitching something too silent up), the timing is good and the generated snippets easily fade into each other without causing any distortions.
If you ask me it's a must have for anyone attempting vasudan voice acting. Its UI is easily understandable and it's easy to adjust for whatever vasudan speech length you require it. No more painfully using and adjusting already existing, low quality vasudan sound samples.
I hope it'll be used widespread, because it reduces adjustment times for voice acting vasudan personas by far!