Acapella group gives you a generous length of time to evaluate the voices -- 30 days of unrestricted use. If you haven't decided whether you can live with the voices after that amount of time, you probably weren't using them in the first place. If, however, you find that you miss the voices after the trial period ends, that's a sure sign that you should purchase the voices.

The American voice pack comes with several voices. However, only the HQ voices are of any real quality. The HD voices sound more robotic than even the low-quality voices that come with the Mac. There are five HQ voices.

However, narrowing them down a bit further, the child voices, Kenny and Nelly, are just high-pitched versions of other voices. That leaves you with three truly high-quality voices, Heather, Laura, and Ryan.

At $99 for the voice pack, that puts the best voices at about $33 each (no you can’t purchase them individually), $13 more than the individual Cepstral voices. The best voice of the bunch, Ryan, however, sounds excellent (aside from a few ideosyncrasies).

The worst trait of the Infovox Ivox voices is that they pronounce some punctuation marks, such as asterisks and dashes. This is especially annoying in e-mails when these characters are used as separators such as:

*********************************************************************

When the voices get to such strings, they insist on stupidly saying, “asterisk asterisk asterisk asterisk asterisk asterisk asterisk asterisk asterisk” ad nauseum.

Apple's voices have not read punctuation marks like these for over a decade. Come on Acapella, what were you thinking? Get with the program! This is ridiculous when a natural sounding voice suddenly starts reading “asterisk asterisk asterisk” or “dash dash dash dash dash dash dash dash dash dash” etc.This is pointless and unnatural. And annoying.