Hi there countrygirls, you could have a look at this article posted recently on CDRinfo that reviews the 1-to-21 duplicator from ACARD - http://www.cdrinfo.com/Sections/Reviews/Specific.aspx?ArticleId=17903
I have had some experience with these units and they are quite simlpe to operate. Everything is done from a 4 button front panel. The Acard unit is indeed 3 boards with one acting as the master and the other 2 as slaves. And from what I see, the model you are thinking of buying from Octave uses ACARD technology. The particular boards can be used separately so that you could have a 1-to-7 or 1-to-14 duplicator if you were thinking of doing it yourself.
As always with these units, the greatest cost is the drives. The controller boards are around US$600 for the three. The problem is that it's very difficult to build your own - you need a rack, power supplies and then to put in everything so that it works. I guess that's why the cost goes up. The Octave unit also has 3x80GB hard disks so that you can copy your compilations onto them, and then from there onto the CD or DVD media.
I know that ACARD also has a USB board that can be used to hook up the duplicator with a PC so that you can controll everything from a PC, although I don't know how this works or how good it is. If you're interested in this type of setup, let me know and I'll see what I can find out.