It's snake oil. Check out the biodieselnow.com forums and search for it. Also tdiclub.com forums. It's gone around a few times. It doesn't actually make biodiesel and a few people more knowledgeable than I have run tests on it and it doesn't make veyr high quality stuff. If you had a mid 80's volvo or MB it would probably be fine but I wouldn't run it through our high pressures common rail systems.
Home BioD reactors can be had for aorund $500. It's not as automated as those $3K systems but you just plan to burn a Saturday once a month making it. Check out the above forums for info.
Personally, I just buy BioD made from waste veggie oil that a group refines into biodiesel. Get to feel even more like a bunny-hugger that way
