I considered using this service, but when I found out that it costs $14.9 cents per minute to record your audio over the phone, I was less than enthusiastic. You can also use the microphone on your computer, which is free. The monthly cost of $29.95 seems a little steep, but it is unlimited use for the month. There are sample auctions at the site so you can get a feel for how it works. I found that most people were recording cheesy things rather than adding to the info in their auction or conveying more trust.
You also have to consider if you want to spend the additional time recording an audio for all of your auctions or just a standard audio for all auctions.
In the end, I decided that my time and money were better spent on other things that would truly enhance my business. I find that most things like audio and templates and animated galleries in auctions distract and irritate buyers more than anything. I'll pass for now.