I have been using the Avia for about a year now and I don't know how I lived without it! IMHO it is essential to have a good reference for calibrating both audio and video, if you don't utilize profesional technitians. Most recievers come with preprogrammed test tones and such, but they don't really work as well as playing test equipment through your A/V source unit. The Avia is a great tool for DIY H/T buffs. I think I got my DVD for like $15 or $20 bucks on amazon I think.
This product has my thumbs up!