Obviously, they're not going to be perfect. But they speak Japanese better than I do at the moment, and they sound pretty good. I find it's more useful for me to use to dump in words I'm not sure about, so I'm not just guessing at how a word is supposed to sound (creating bad input), so that alone is worth the money for me.
I don't *just* do this-- I also watch TV programs, I listen to podcasts, etc. I would NOT recommend doing any one thing in isolation, anyway.
BUT for uses where you want to know how a word "sounds," this is extremely useful. If you have Misaki already, and it works for you, and you can't afford the $35 for Show, then just stay with Misaki for now.
The Show voice sounds pretty much like what it sounds like on the website. It's a little less polished than Misaki, but it does have an easier voice range for me to follow along with. (I studied a lot of music growing up, so my voice training will kick in and I'll try to match Misaki's pitch out of instinct, so I wind up with my voice in weird registers.)
I was looking at the company's website, and they mentioned that the voices they sell vary in bit-rate sampling, (8, 11, and 16 kHz), as well as database footprint (from 16MB up to 500MB). From my experience, the Miyu and Show voices I bought were 16/500, so they were the same as the top of the line offered. Misaki is supposedly available in similar bit-rates and db sizes, so I don't know why there might be a difference between the server and your system, but it could be just about anything from sound cards to processor speed.
I have noticed that sometimes Misaki sounds smooth, and other times, she sounds a little rough around the edges. Who knows why. I'm not really too picky about that. I just find it easier to do it this way than to try to hunt down Japanese people at 11 at night when I just want to get a rough idea of how a word sounds.
The thing is, these voices have come so amazingly far compared to how they used to be, I'm not going to complain about it (too much.)
EDIT: If you're converting text to MP3-- then be forewarned. The quality of the MP3s TextAloud generates is horrid. The WAV files are perfect. If you're basing the quality of the voices on the MP3s, then I can totally see your point. I'd say save them as WAVs, and find a better program to use to rip them into MP3s. I don't create a lot of sound files myself-- I just dump text in the box and have it speak it out abit.
Edited: 2008-05-10, 11:30 am